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Plant Nutrient Additives


Dr Greenthumb
Dr Greenthumb
Dr Greenthumb

A garden needs nutrients to thrive - we all know this, but what science is teaching us is that no 1 fertilizer provides everything plants need to reach their optimum growth and production.

This is where nutrient additives (supplements) come in - they contain those quirky hormones, acids, enzymes and other unique tidbits that round out your garden's nutritional diets...

If you prefer to see a price list go here


  Age Old Organics Fish and Seaweed 

Age Old Fish and Seaweed is an organic fertilizer that works well in both soil and hydroponics. 

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  Age Old Organics Humic Acid 12 

Age Old Humic Acid 12 liquid is 100% organic. Humic acid is used to reclaim soils damaged by chemicals. 

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  Age Old Organics Promote 

Age Old Promote Root Zone Management is a combination of Humates, seaweed extract and wetting agents designed to work in harmony to break the chemical bonding of tied-up mineral nutrients in the root zone. 

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  Algamin Kelp Meal 

Algamin Kelp Meal is a rich organic source of nitrogen and potassium. Algamin is fresh-cut Norwegian seaweed slowly, mechanically dried, cleaned, desalted and ground into dust-free meal. 

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  Algen Extract 

House & Garden Algen Extract promotes vigorous vegetative growth as well as aiding plant nutrient uptake. 

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  All Nectar for the Gods package 

Because the Nectar for the Gods line of nutrients works so well if you use all of the parts, we decided to offer an extra discount for anyone interested in picking up the entire line in one bulk order. 

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  Amino Treatment 

House and Garden Amino Treatment helps increase chlorophyll concentration in the plant, leading to a higher degree of photosynthesis. Increased photosynthesis makes crops lush and green, increasing plant vigor and overall yields. 

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  Ancient Amber 

Roots Organics Ancient Amber is specially extracted for low molecular weight from Leonardite, a rare form of lignite coal composed of ancient plant material. 

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  Aphrodites Extraction 

Nectar for the Gods Aphrodites Extraction is rich in organic acids to enhance enzymatic activity. 

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  Athenas Aminas 

Nectar for the Gods Athenas Aminas is a fully water soluble amino acid supplement. 

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  Azos 

Xtreme Gardening Azos acts as a growth stimulant, catalyzing the release of a natural hormone (Idole-3 Acetic Acid) in plants. This naturally-released hormone increases root development and optimizes the harvest potential of your garden. 

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  B`CuzZ Bio Stimulant Booster Pack 

The B`Cuzz Booster Pack is a set of gardening stimulants to help take your plants from start to finish. Simply add them to your existing fertilizer program to get amazing results. 

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  B`CuzZ Bio Stimulants 

The B'CuzZ Stimulator products are tailored to work sequentially with each other through the growing stages and maintains the biological balance while maximizing growth. With B`CuzZ, the professional grower can stimulate the plant from seed or cutting to mature plant with rapid and efficient fission, cell expansion, and cell differentiation (lots of produce!). B'cuzZ grown plants are excellent for cloning. 

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  B`CuzZ Blossom Builder Tabzz 

B'Cuzz Blossom Builder Tabzz are 100% sizzling flower multipliers that ensure an explosive flower development in the flower phase. 

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  B`CuzZ PK 13-14 

Atami manufactures B`Cuzz PK 13-14 Bloom Booster from food grade quality raw materials. This high quality flowering preparation with Phosphorous and Potassium will stimulate amazing floral development very rapidly. 

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  B-52 Fertilizer Booster 

Ever taken B Complex vitamins to ease stress and put yourself back on track? Plants have the same reaction to the B vitamin family! That's why Advanced Nutrients formulated B-52 Fertilizer Booster. 

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  Beastie Bloomz 

FoxFarm Beastie Bloomz is a heavy-weight blossom builder that fortifies the inside portion of your flower buds to increase the weight of both blooms and fruit set. This is a high-phosphorus dry formula that is completely water soluble. 

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  Bee One Aqua 

Bee One Aqua is rich in natural plant hormones, vitamins, enzymes, and amino acids, all essential for explosive growth. 

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  Big Bud Bloom Booster Liquid 

Big Bud Bloom Booster Liquid is made with the correct ratio of potassium, phosphorus, magnesium and sulphur, the superfoods that stoke the floral production system in your plants. 

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  Big Bud Bloom Booster Powder 

Big Bud Bloom Booster Powder contains all of the amino acids that are the essential foundation for plant metabolism and flower growth. It also has ascorbic acid to stimulate the metabolic processes in your plants. 

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  BioAg CytoPlus 

A combination of soluble seaweed extract and seven micronutrients, BioAg CytoPlus is an excellent source of beneficial organic compounds, including humic and fulvic acids. 

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  BioAg Ful-Power Humic Acid 

Often referred to as the champagne of humic acids, BioAg Ful-Power Humic Acid is an excellent choice for all gardening applications. 

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  BioAg HumiSolve Humic Acid Concentrate 

BioAg HumiSolve is a water soluble humic powder and soil/nutrient activator. It increases nutrient efficiency and uptake, increases cellular activities at all levels. 

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  BioBizz Alg-A-Mic 

Alg-A-Mic, from BioBizz, is a high-grade organic seaweed concentrate extracted through cold-press. Alg-A-Mic can be used as a nutrient supplement or as a foliar spray. 

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  BioBizz BioHeaven 

BioBizz BioHeaven contains biological stimulants, such as amino-acids. Amino-acids are the basic building blocks for the proteins and enzymes, which are essential to the structure and the metabolism of your plants. 

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  BioBizz RootJuice 

RootJuice is a 100% vegetable root stimulator that creates explosive root growth in existing rooted plants through the stimulation of the natural microbiology surrounding the root system. 

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  BioBizz TopMax 

TopMax, from BioBizz, is a 100% organic bloom stimulant comprised of the pure essence of special flowers, sea kelp and leonardite. 

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  BIOCANNA Bio Boost 

BIOCANNA Bio Boost is a naturally fermented plant extract that is 100% organic. Developed for use during the blooming stage, this supplement stimulates the development of newly formed flowers to generate fuller fruit with more flavor! 

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  Blast-Off Fertilizer 

Contains high potency natural vitamins and hormones that act as cofactors or substrates for specific plant enzymes. 

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  Bloom Fuel 

Grotek Bloom Fuel is a unique flower triggering solution designed to ease your plants out of the vegetative stage and switch them over to the flowering stage. 

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  Bloom Khaos 

Nectar for the Gods Bloom Khaos encourages increased flower sites, tighter internodes, and larger flowers. 

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  Bloombastic® 

The Bling Bling for your plants! Bloombastic® is for you serious growers! Bloombastic will elevate the performance of any brand of base nutrient to a master gardeners level. 

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  Blossom Blaster 

Blossom Blaster is a powerful blend of phosphorous and potassium fertilizers created for explosive flower development in your plants. 

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  Botanicare Cal-mag Plus 

Cal-Mag Plus is a beneficial nutrient supplement that corrects calcium, magnesium, iron and trace mineral deficiencies found in most soil fertilizers and some hydroponic nutrient liquid concentrated formulas. 

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  Bud Candy 

Advanced Nutrients Bud Candy was created by combining both Sweetleaf and Carbo Load into one powerful flavor and aroma enhancer that will also give you even bigger yields. 

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  Bud Factor X 

Advanced Nutrients Bud Factor X is a liquid hydroponics bud builder formula that is guaranteed to increase crop yields and essential oil production by stimulating plant defense mechanisms. 

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  Bud Ignitor 

Advanced Nutrients Bud Ignitor lets you maximize the flowering sites per stem! Advanced Nutrients has developed Bud Ignitor to give you extreme results when triggering the flowering phase of your plants. 

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  Bud XL 

House & Garden Bud XL is an innovative late bloom additive that focuses on increased fruit and flower production. 

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  Bush Master 

Humboldt County's Own Bush Master stops vertical plant growth in it's tracks. Our customers have seen immediate results! 

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  BushDoctor Kangaroots Root Drench 

FoxFarm BushDoctor Kangaroots is an organic macro and micronutrient formula that enhances both primary and secondary root development. It also contains concentrated amounts of microbes to enrich soil or growing medium! 

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  BushDoctor Sledgehammer 

FoxFarm BushDoctor Sledgehammer fertilizer rinse is designed to remove excess fertilizer buildup to improve water movement through both soil and soilless growing mediums. 

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  CalCarb Foliar Spray 

Xtreme Gardening CalCarb is a foliar spray derived from naturally existing calcium carbonate. It provides the carbon dioxide needed to achieve optimum photosynthesis performance – effectively maximizing your plants growing potential. 

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  CALiMAGic™ Calcium Magnesium Supplement 

General Hydroponics CaliMagic is a concentrated blend of readily available Calcium and Magnesium which helps support fast growing plants by preventing secondary nutrient deficiencies. 

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  CANNA Cannazym 

CANNA Cannazym stimulates the break down of dead root material through the use of 12 different kinds of enzymes. It also contains vitamins and desert plant extracts to help activate beneficial micro-organisms. 

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  CANNA PK 13/14 Flower Stimulator 

CANNA PK 13/14 was developed to stimulate the flowering phase of fast growing plants. This high grade mixture of phosphorus and potassium allows your plants to lavishly flower and fruit. 

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  Carbo Load 

To sustain optimum health, plants need to load up on carbohydrates during the production phase as their stored carbs are drained while producing flowers, fruits, nuts, herbs and vegetables. 

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  Cha Ching 

FoxFarm Cha Ching improves the taste and aroma of your garden fruits and vegetables by concentrating the plant oils. 

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  Crystal Burst Bloom Enhancer 

Humboldt County’s Own Crystal Burst is a high-potency bloom enhancer with vitamin B1. 

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  Cutting Edge Solutions Mag Amped 

Are your plants suffering from short daylight hours or low light intensity? Mag Amped is your solution! 

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  Cutting Edge Solutions Plant Amp 

Developed by Cutting Edge Solutions, Plant Amp is pure calcium, chelated with organic acids to improve plant absorption. Use it in your reservoir or as a foliar spray. 

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  Cutting Edge Solutions Sour-Dee 

Cutting Edge Solutions Sour-Dee stimulates amino acid production in your plants. 

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  Cutting Edge Solutions Uncle John's Blend 

Uncle John’s Blend is used throughout your plant's growing cycle to supply potassium to plants, delivered through a matrix of sugars (carbohydrates). 

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  Dark Energy 

American Hydroponics Dark Energy significantly shortens your time-to-harvest while increasing plant yields. It helps plants absorb the benefits of fertilizers so you can lower the amount of fertilizer you are using. Many growers have reported seeing a difference within 24 hours! 

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  Demeters Destiny 

Nectar for the Gods Demeters Destiny is liquid calcium derived from Calcium Phosphate. 

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  Diamond Black 

General Organics Diamond Black is derived from 100% pure mined Leonardite, a naturally occurring form of carbon drawn from prehistoric peat bogs. 

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  Diamond Nectar 

Contains the highest quality, most effective fulvic acid available and is safe to mix with hydroponics solutions, soil, or foliar applied fertilizers. 

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  Drought and Frost Protection Plus 

Drought and Frost Protection Plus allows gardeners to provide natural, cellular level protection for plants under adverse conditions. 

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  Dutch Master ADD.27 Flower and Grow 

Dutch Master Gold Range ADD.27 is a mineral based nutrient additive with amino acids that will optimize the rate of cytoplasmic streaming (how a plant delivers nutrients to its cells). 

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  Dutch Master Silica 

Dutch Master Gold Range Silica is a silicon supplement that helps strengthen plant cell walls. Silicon improves the overall health of your plants so they can more easily resist insects, drought, disease, heat and other stress related conditions. 

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  Dutch Master Zone 

Many root cleansing and sanitizing products, such as hydrogen peroxide, can be too harsh for your plants. Dutch Master Gold Range ZONE is a gentle and effective alternative to water sanitization and can be used throughout the life of your garden. 

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  Dyna-Gro Mag-Pro 

Dyna-Gro Mag-Pro is an award winning blossom booster that gives outstanding results when used on orchids, roses and other indoor or outdoor flowering plants. 

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  Dyna-Gro Pro-TeKt 

Dyna-Gro Pro-TeKt gives your plants higher levels of potassium and silicon to help build strong cell walls. 

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  Earth Juice Assist wetting agent 

Earth Juice Assist is a natural wetting agent and media conditioner. Use Assist to soften soils for better moisture penetration and to increase fertilizer availability. 

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  Earth Juice Catalyst Activator 

Earth Juice Catalyst is a 100% organic additive that conditions soils and hydroponic solutions for better nutrient availability. 

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  Earth Juice Escential Spray 

Earth Juice Escential Spray is a natural aromatic scent concentrate consisting of aromatic botanical extracts. 

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  Earth Juice Meta-K Potassium Fertilizer 

Earth Juice Meta-K is a 100% natural liquid potassium nutrient for maturing, fruiting, and flowering plants that require more potassium. 

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  Earth Juice Microblast Minerals 

Earth Juice Microblast is a proprietary liquid micronutrient formula to be used to prevent and correct micronutrient deficiencies. 

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  Ecklonia Kelp Plant Growth Stimulant 

Ecklonia Kelp Plant Growth Stimulant is a 100% organic nutrient supplement that is made from Ecklonia Maxima, an edible species of brown kelp seaweed. It is completely non-toxic to humans, animals, birds and insects. 

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  Equilibrium Natural Ca-Mg 

Humboldt Nutrients created Equilibrium Natural to give you an easy to use one-part calcium and magnesium additive in the correct ratios to produce strong healthy plants. 

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  Espoma Organic Traditions Bone Meal 

Espoma Organic Traditions Bone Meal is an all natural source of organic phosphorous and nitrogen. 

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  Espoma Organic Traditions Dried Blood 

Espoma Organic Traditions Dried Blood is a safe source of organic nitrogen. 

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  Espoma Organic Traditions Garden Gypsum 

Espoma Garden Gypsum is a 100% organic product that helps counteract soil damage caused from salt used in winter de-icing. 

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  Espoma Organic Traditions Greensand 

A mineral-based soil amendment, Espoma Greensand is rich in the conditioning element glauconite, a marine material composed primarily of iron-potassium silicate. 

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  Espoma Organic Traditions Rock Phosphate 

Espoma Organic Traditions Rock Phosphate is a 100% natural source of phosphorus. Plants require this nutrient for healthy root development and for fruit and flower production. 

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  Final Phase Clearing Flush Solution 

Final Phase clearing flush solution removes excess hydroponic nutrients, heavy metals and pollutants from your plants' root zone. 

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  Floralicious Grow / Floralicious Bloom 

Floralicious Bloom and Floralicious Grow, from General Hydroponics, brings out your plant's full genetic potential by augmenting metabolic activity in the root zone. This potent organic nutrient additive is made from the best nature has to offer! Floralicious contains a perfect balance of vitamins, phytohormones, humic acids, polysaccharides, fructans, beta-glucans, L-amino acids, and polyflavonoids. 

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  Floralicious Plus 

Floralicious Plus contains the organic building blocks of life. It enhances metabolic growth and essential oil production, promotes flower development, stimulates fruit swelling and encourages beneficial microbial activity in the root zone. 

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  FloraNectar Sweetener 

General Hydroponics FloraNectar Sweetener optimizes the largest transference of sweetness and aroma into your fruits and flowers. It fulfills the additional energy requirements of your plants throughout all phases of growth, and during stressful times of transition. 

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  FossilFuel 

Europonic FossilFuel from Hydrodaynamics helps plants resist environmental stress, diseases and pests. Use as a nutrient solution or a foliar spray. 

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  FoxFarm Soluble Tri-Pak Nutrients 

The FoxFarm Soluble Tri-Pak includes everything to supercharge the flower potential in any garden! 

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  General Organics BioBud® Bloom Booster 

General Organics BioBud is a powerful bloom stimulator that produces a larger number of flowering sites. 

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  General Organics BioMarine® 

Part of the General Organics (GO) line from General Hydroponics, BioMarine is a fish-based fertilizer that encourages and supports beneficial microbes to improve soil vitality. 

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  General Organics BioRoot 

BioRoot is a nutrient supplement that helps your plants develop stronger, larger root systems for improved overall plant health. 

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  General Organics BioWeed 

Part of the new General Organics (GO) line from General Hydroponics, Bio Weed takes advantage of cold processed seaweed to promote natural intense vegetative growth. 

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  General Organics CaMg+ 

CaMg+ is a plant supplement that provides a natural source of calcium and magnesium, elements that are critical during your plants' growth cycle. 

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  Giant Pumpkin Growing Kit 

The Xtreme Gardening Giant Pumpkin Growers Kit includes everything you need to a grow a potentially record breaking pumpkin naturally! 

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  Ginormous Bloom Enhancer 

Humboldt Nutrients specifically formulated Ginormous Bloom Enhancer to help your favorite plants yield the largest fruits, higher brix levels and better aromas. 

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  Grandma Enggy's F-1 Fulvic Acid 

100% organic! Grandma Enggy's F-1 helps your plants grow faster and produce higher quality harvests. It increases nutrient absorption, nutrient transport, and more cellular metabolism than any other Fulvic extract. 

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  Grandma Enggy's H-2 Humic Acid 

Grandma Enggy's H-2 Humic Acid is 100% organic magic! Rich in several minerals needed for optimum plant growth, it helps convert a variety of elements into easily absorbed forms for healthy crops. 

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  Gravity Flower Hardener 

Gravity Flower Hardener contains active amino acids that can increase the size and mass of your flowers, fruits and vegetables! Our customers say they see the difference in just 1 or 2 days. 

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  Great White Mycorrhizal 

Great White is simply the best mycorrhizal product of it's kind! 

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  GreenFuse Bloom Stimulator 

Hydrodynamics International GreenFuse Bloom Stimulator is 100% organic. It invigorates the natural blooming cycle of your plants, resulting in flowers and fruits with superior aroma and flavor. 

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  GreenFuse Growth Stimulator 

Hydrodynamics International GreenFuse Growth Stimulator is an organic nutrient supplement to be used during the vegetative growth stage of your plants. 

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  Grotek Heavy Bloom 

Designed to be used during the reproductive stage of your garden, Heavy Bloom™ nutrient supplement increases the size and weight of fruit and flowers! 

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  Grotek Monster Bloom and Monster Grow 

Grotek Monster Grow and Bloom are the perfect blend for your indoor hydroponics garden. 

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  Grotek Pro-Silicate 

Grotek's Pro-Silicate™ is a nutritional silicate additive containing potassium and silicon. This combination of ingredients acts as a tranpirant to help increase your plants' resistance to heat and drought. (A must for cloning.) 

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  Herculean Harvest 

Nectar for the Gods Herculean Harvest increases the availability of calcium and phosphorus to promote prolific blooming. 

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  Hesi COCO Supplement 

Using Coco as your garden's growing medium? You'll want to add Hesi Coco during the entire plant's life for maximum results! 

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  Hesi HYDRO PK 13/14 

During the flowering stage of a plant's life, its metabolism is pushed into high gear producing large amounts of enzymes. It continues to grow larger increasing the need for nutrients to keep it healthy. That's where Hesi PK 13/14 comes in. 

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  Hesi Root Complex 

Like a shot from the doctor's office, Hesi Root Complex helps heal ailing plants. A mix of trace elements that include vitamins, amino acids, plant sugars and enzymes, Root Complex is ideal for combating the stress of repotting and clone cutting. 

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  Hesi SOIL Phosphorus Plus 

Combined with Bloom Complex, Hesi Phosphorus Plus insures maximum flowering results of plants potted in soil. 

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  Hesi Super Vit 

Hesi Super Vit is a concentrated mix of 15 vitamins and 10 amino acids that increase your plants metabolism and overall health. 

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  Hi-Brix Molasses 

Earth Juice Hi-Brix Molasses is a highly prized molasses that is a natural source of carbohydrates and plant nutrients. 

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  Hormex Root Stimulant Liquid 

Hormex root stimulator is a liquid vitamin and hormone concentrate that encourages new root growth. 

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  Humboldt Honey HYDRO Carbs 

Humboldt Hydro Honey Carbs is an excellent source of carbohydrates for all plants grown hydroponically. It breaks down into the smallest possible sugars when dissolved in water, creating an easily accessible food for beneficial fungus, bacteria, and plants. 

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  Humboldt Honey Organic ES 

Humboldt Honey Organic ES (Extra Strong) is an excellent source of carbohydrates for all plants. 

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  Humboldt Nutrients Big Up Powder 

Humboldt Nutrient's Big Up Powder provides the final boost of energy that plants need to finish the bloom cycle with impressive results. This premium amino chelated bloom booster has no unnecessary artificial colors or dyes. 

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  Humboldt Nutrients DueceDuece 

Organic DueceDuece, from Humboldt Nutrients, contains large amounts of potassium derived from Probiotic Potassium, and Sulfate Of Potash. 

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  Humboldt Nutrients FlavorFul 

Humboldt Nutrients' FlavorFul is 8% fulvic acid - much stronger than others in the market. The dark amber color confirms the high concentration! 

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  Humboldt Nutrients Royal Flush 

Use Humboldt Nutrients Royal Flush to produce the cleanest, sweetest, most flavorful harvests. 

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  Humboldt Nutrients Sea Cal 

Humboldt Nutrients' Sea Cal is a powerful fertilizer additive designed for hydroponics gardening, with any growing medium. Safely use it on your vegetables, flowers, or herbs! 

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  Humboldt Nutrients Sea Mag 

Humboldt Nutrients’ Sea Mag is loaded with vital micro-nutrients, plant hormones and B-vitamins! Cytokynins and auxins are also provided by the sea plant extracts and organic acid complexes. 

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  Humboldt Nutrients Structural Integrity 

Humboldt Nutrients Structural Integrity (S.I.) is a silicate supplement designed for use with hydroponics systems but can be used with soil. 

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  Humboldt Nutrients Verde 

In Spanish, verde translates into green, and green is what you'll get when you use Humboldt Nutrients' Verde in your garden! This one-part organic growth catalyst can also be used as a foliar spray with either hydroponics or soil-based gardens. 

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  Humboldt Roots 

Made by Humboldt Nutrients, Humboldt Roots is a highly concentrated root stimulant that expands the root zone during the critical growth stage. 

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  Hum-Bolt Liquid Humic Concentrate 

For years Humic Acid has been largely absent from our soil, due to erosion and over-farming and has long been missing in our food chain. 

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  Hydroplex Bloom Maximizer 

Hydroplex Bloom Maximizer is a premium plant supplement used during the reproductive fruiting and flowering phase of a plants life cycle. Replacing Hydroplex Bloom Enhancer, this new balanced formula is effective for both hydroponics and soil. 

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  Hygeia Hydration 

Nectar for the Gods Hygeia Hydration is the blending tool for this line of plant nutrients. 

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  Killer Tea 

Made from OMRI worm castings and guanos, Humboldt County’s Own Killer Tea is all natural. 

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  KoolBloom Dry Supplement 

KoolBloom Dry Ripening Formula is a highly concentrated dry nutrient supplement that promotes lavish flowering and encourages ripening in annual flowers and herbs. 

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  KoolBloom Liquid ripening formula 

Just like its dry counterpart, Liquid KoolBloom ripening formula is a highly concentrated additive that helps initiate ripening in annual flowers, perennial flowers and herbs. It also increases the size and weight of both fruits and flowers. 

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  Liquid Humus 

Liquid Humus is an excellent natural organic source of concentrated essential nutrients, vitamins and trace elements. 

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  Liquid Karma 

Liquid Karma functions as a growth engine because its high metabolic activity produces a large amount of energy, which is immediately transformed to growth. This Bio-catalyst plant stimulant contains a full complement of metabolically active organic compounds not found in regular plant foods or supplements. 

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  LXR Gold organic supplement 

Grotek LXR Gold is an organic liquid supplement that assists nutrient uptake and distribution within a plant. Works well in soil or hydroponics gardening. 

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  Magic Green 

House & Garden Magic Green is a foliar spray that nourishes your plants from the outside in, helping to green-up plants during any growth phase. 

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  Maxicrop Liquid Fish 

Maxicrop Liquid Fish is made of fresh fish from the Atlantic Ocean and contains no chemical additives. Maxicrop Liquid Fish contains naturally occurring amino acids, as well as a huge complex of chelated minor elements (especially B vitamins). 

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  Maxicrop Liquified Seaweed 

Maxicrop Liquified Seaweed is made from pure seaweed extracts containing natural growth stimulants which initiate cell growth and cause vigorous growth of both root and stem. Maxicrop Liquified Seaweed organic plant fertilizer works well for both indoor and outdoor gardening. 

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  Maxicrop Liquified Seaweed Plus Iron 

Maxicrop Liquified Seaweed Plus Iron contains 2% iron. A unique combination of pure seaweed extract with readily sequestered iron in an easy-to-use liquid form. This high iron formulated product, when sprayed directly onto foliage, or applied as a root drench will prevent yellowing (chlorosis) of leaves, especially in acid-low (calcifuge) plants. 

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  Maxicrop Soluble Seaweed Powder 

Maxicrop Soluble Seaweed Powder stimulates beneficial soil microbe activity which helps improve your garden's natural resistance to stress. It also extends the root system to give your plants greater access to nutrients and water in the soil for improved long term health. 

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  Mayan MicroZyme 

Mayan MicroZyme, from Humboldt Nutrients, is a 100% organic and ecologically safe bacterial-enzymatic complex that decreases the risk of disease causing bacteria. 

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  Mega Morpheus 

Nectar for the Gods Mega Morpheus is a readily available source of natural phosphate for your plants that is completely water soluble. 

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  Multi Zen 

House & Garden Multi Zen is a concentrated growth additive whose unique formulation helps to thicken stalks resulting in stronger, more vigorous plants. 

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  Myco Madness Soluble 

Made by Humboldt Nutrients, 100% organic Myco Madness contains a biologically active package, 8 mycorrhizal species, 12 beneficial bacteria and 2 Trichoderma species well-suited to a variety of media, soil conditions, climates and plants. 

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  Myco Maximum Granular 

Myco Maximum granular is an organic biological innoculant that contains 8 species of growth-enhancing mycorrhizal fungi, 12 strains of beneficial bacteria, 2 Trichoderma species, plus other proprietary ingredients (humic acid, carbohydrates, amino acids). 

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  Mykos Drops 

Xtreme Gardening Mykos Granular Mycorrhizae Drops are an easy, efficient method of applying beneficial microbes to any garden. 

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  Mykos Granular 1 lb 

Xtreme Gardening Mykos Pure, Fresh Alive is a granular form of beneficial organism, Mycorrhiza (plural: Mycorrhizae), that lives on the roots of plants to form a healthy symbiotic relationship. 

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  Mykos Granular 100g Singles 

This single application size of Xtreme Gardening Mykos Pure, Fresh Alive is a granular form of beneficial organism, Mycorrhiza (plural: Mycorrhizae), that lives on the roots of plants to form a healthy symbiotic relationship. 

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  Mykos Wettable Powder (WP) 

Xtreme Gardening Mykos WP (Wettable Powder) provides an effective Biological Inoculant that may be injected through a sprayer, applied in hydroponic reservoirs, and used as a seed or cloning treatment. 

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  Neptunes Harvest Crab Shell 

Neptune's Harvest Crab Shell is an excellent organic source of nitrogen, phosphorous, calcium (23%), and magnesium (1.33%). The high calcium content and slow release nitrogen and phosphorous makes this a good fertilizer when planting bulbs in spring and fall. A safe, natural slow-release fertilizer, Crab Shell also helps with nematode and fungus problems. 

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  Neptunes Harvest Kelp Meal 

Neptune's Harvest Kelp Meal is Ascophyllum Nodosum, which is widely recognized as one of the finest marine plants available for agriculture today. Kelp Meal contains vitamins, minerals, carbohydrates enzymes, amino acids and growth hormones necessary for optimum plant growth. Since it is 100% organic, this fertilizer won't burn plants or roots, plus it is environmentally safe! 

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  Neptune's Harvest Seaweed 

Neptune's Harvest Seaweed fertilizer supplement is an organic storehouse of over 60 naturally occurring major and minor nutrients and amino acids. 

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  Nirvana Bloom Biostimulant 

Nirvana Bloom Biostimulant, from Advanced Nutrients, is 100% organic! Created specifically for hydroponics gardening, Nirvana provides bloom-swelling stimulants that increases flower aroma and grows larger, better tasting fruits or vegetables.  

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  Nitron A-35 soil conditioner 

Nitron Formula A-35 is an organic soil conditioner that enhances your fertilizers while restoring life to deficient soil. While improving soil texture, this 100% natural enzyme liquid makes more nutrients and trace elements available to your plants by breaking up clay or hardpan soils to help increase microbial action. 

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  Nitrozime Marine Algae Extract 

Nitrozime stimulates plant growth by increasing cell division which improves yield by decreasing plant stress. Nitrozime is also effective as a seed treatment. Cytokinins, the natural plant growth hormones which are necessary for plant growth, nutrient mobilization and distribution, germination, cell division, root development, flowering and seed formation are the core of Nitrozime formulation. 

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  Nutrilife H2O2 

Nutrilife H2O2 is a quick and easy way to oxygenate the nutrient solution in your reservoir. 

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  Open Sesame 

FoxFarm Open Sesame is a full spectrum blend of micronutrients specifically developed to trigger early flowering and ripening in fruits, buds, and flowers. 

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  Orca Liquid Mycorrhizae 

Plant Success Orca is a biological inoculant developed for hydroponics gardeners. 

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  Oregonism XL 

Roots Organics Oregonism XL is a distintive blend of endo/ecto-mycorrhizae, beneficial bacteria, and Trichoderma. 

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  Organa-Guano Liquid 

Organa-Guano, from Higrocorp, is effective for hydroponics, aeroponics and soil cultivation. This multi-use additive stimulates early flowering and maximizes the size and weight of both fruit and flowers. 

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  Organic B 

Advanced Nutrients Organic B helps plants handle the stress of intense hydroponic gardening. This 100% organic nutrient supplement contains a wide range of B vitamins that strenghtens your crops by promoting faster nutrient absorption. 

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  Overdrive Flower Enhancer 

Advanced Nutrients Overdrive was developed with an extensive and complex array of phosphorus and potassium sources. Hormones and catalytic agents are included to help stimulate your plants' bloom productivity. 

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  Pegasus Potion 

Nectar for the Gods Pegasus Potion feather tea is a new concept of nitrogen delivery for your plants. 

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  PhosphoLoad 

Dutch Master PhosphoLoad halts the vertical growth of your plants to create a more bushy structure. 

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  Plant Success Mycorrhizae granular 

Mycorrhizal is a soil-dwelling fungus that lives in and around the roots of plants. The fungi and the plants form mutually beneficial associations in which the fungi receive carbohydrates from the plants and the plants receive nutrients and other benefits from the fungi. 

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  Plant Success Mycorrhizae tablets 

Mycorrhizae is a soil-dwelling fungus that lives in and around the roots of plants. The fungi and the plants form mutually beneficial associations in which the fungi receive carbohydrates from the plants and the plants receive nutrients and other benefits from the fungi. 

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  Plant Success Soluble Mycorrhizae 

Plant Success Soluble Mycorrhizae is a rich source of 13 strains of beneficial mycorrhizae fungi which are known to reduce transplant shock, fertilizer usage, and increase resistance to root disease. 

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  Plantacillin Biological Water Treatment 

Plantacillin contains a naturally occurring bacteria, Bacillus subtilis GB03, that encourages stronger, denser root mass and length. As we all know, the stronger the roots, the stronger the plant! 

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  Poseidonzyme 

Nectar for the Gods Poseidonzyme (Notrozyme) is a 100% organic liquified seaweed supplement rich in organic acids and over 60 naturally occurring major and minor nutrients and amino acids. 

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  ProZymE Biological Inoculant 

Made by California based Humboldt Nutrients, ProZymE is an all natural concentrated enzymatic formula containing more than 80 different enzymes. 

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  Pure Blend - Original Formula 

Botanicare's Pure Blend Original Formula is a hydro-organic compost solution blended with select ingredients from the land and sea. It reduces plant stress caused by severe environmental conditions, such as heat, frost and drought. 

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  Pure Flowers 

There is no other flowering supplement like Pure Flowers. It's got Phosphite Technology which Higrocorp invented. The unique molecular structure of a phosphite is easily absorbed through the roots and leaves ensuring the crop instantly uptakes potassium and phosphorus. 

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  Quality Cure 

Supernatural Quality Cure is a Dehydrant that safely removes water from your hydroponically grown plants. 

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  Rapid Start Rooting Enhancer 

General Hydroponics Rapidstart rooting enhancer promotes prolific root growth while maintaining root pliability so they will not break during tranplanting. 

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  Rare Earth Organic Clay and Humic Acid 

Rare Earth, from General Hydroponics, is a premium blend of dry organic minerals and humates that is derived from ancient seabed deposits of pyrophyllitic clay that are blended with fulvate ore. 

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  Revive Crop Repair Formula 

When your garden is ailing, get the hospital in a bottle! Revive Crop Repair Formula is loaded with safe forms of iron and other rejuvenating nutrients to save your crop. 

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  Rhino Skin 

Advanced Nutrients Rhino Skin is derived from Potassium Silicate to help strengthen plant cell walls. The stronger the cell walls, the sturdier the plant. 

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  Root 66 

Formulated to promote explosive root development, Technaflora's Root 66 improves your plants ability to successfully absorb water and nutrients. 

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  Rootbastic Root Stimulator 

From the makers of B`CuzZ, Atami Rootbastic is a concentrated root stimulator with a combination of high NPK bio stimulants and Bio minerals. 

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  Roots Excelurator 

The ingredients in House & Garden Roots Excelurator are a closely held secret, but expect amazing root development when you use this root enhancer! 

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  Roots Organics Trinity Catalyst 

Roots Organics Trinity Catalyst is a complex liquid blend of organic compounds specifically designed for maximum effect as a plant, root, and rhizoshpere catalyst. 

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  Roots Organics Extreme Serene 

This organic liquid kelp extract gives your garden a natural source of growth-promoting compounds and micro-nutrients. 

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  Roots Organics HP2 Liquid Bat Guano 

Roots Organics HP2 Bat Guano is an extracted source of natural phosphorous specifically designed to enhance flower quality. 

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  Roots Organics HPK Bloom Booster 

Developed by Aurora Innovations, Roots Organics HPK bloom booster is a specially extracted natural source of phosphorus and potassium to maximize yields and flavors. 

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  Rootstock Cloning Gel and Solution 

For amazing results, dip your plant cutting into Earth Juice Rootstock gel and put into a growing media soaked with Rootstock Solution. 

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  Sensi Cal Bloom™ 

Sensi Cal Bloom is a nutrient additive rich in calcium and magnesium. It was created by Advanced Nutrients for use during the blooming phase of your plants. 

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  Sensi Cal Grow™ 

Plants with calcium deficiencies suffer from slower growth, sickly roots and a geater risk for disease. Advanced Nutrients Sensi Cal Grow is a nutrient additive rich in calcium and magnesium that helps prevent these weaknesses. 

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  Shooting Powder 

House & Garden Shooting Powder is a late flowering additive. It helps to induce a second surge of flower production during the last three weeks of the flowering cycle. 

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  Silica Blast 

Botanicare Silica Blast Plant Bio-mass Yield Enhancer stengthens plant tissue so they can flourish in adverse environmental conditions such as heat, drought, and frost. 

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  Snow Storm Ultra 

Emerald Triangle, the maker of Humboldt County's Own nutrients, has separated Snow Storm from the original Purple Maxx product and supercharged it to create Snow Storm Ultra. 

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  Soul Synthetics Amino Aide 

Aurora Innovations Soul Synthetics Amino Aide helps super charge your plants during the growth and early flowering stages. 

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  Soul Synthetics Big Swell 

Aurora Innovations Soul Synthetics Big Swell bloom booster was engineered to specifically increase the vigor, density and quality of your flowers. 

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  Soul Synthetics Grow-N 

Aurora Innovations Soul Synthetics Grow-N nitrogen booster is for the hydroponics or soil gardener that wants faster plant growth. 

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  Soul Synthetics Infinity 

Aurora Innovations Soul Synthetics Infinity was formulated to provide the higher levels of micronutrients needed for fast growing, heavy feeding plants. 

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  Soul Synthetics PeaK 

Aurora Innovations Soul Synthetics PeaK bloom finisher contains sufficient phosphorus and potassium to encourage lush dense flowering. 

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  SubCulture B Bacterial Root Inoculant 

General Hydroponics SubCulture B is a biological root inoculum that contains 52 constructive gardening microorganisms. These microbes are cultured to live in high salt content environments making them ideal for containized gardening. 

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  SubCulture M Mycorrhizal Root Inoculant 

General Hydroponics SubCulture M is a mycorhizae root inoculant which contains a wide variety of endo and ecto mycorrhizal fungi. 

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  Super Charger 

Super Charger is a vitamin packed supplement for your plants. Each capsule contains a blend of vitamins, antioxidants, peptides and trace minerals. Super Charger will take your plants to a new level of growth and vitality. 

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  Supernatural Brand Ultimate Thrive 

Supernatural Brand Ultimate Thrive is a pure blend of vitamins, minerals, plant nutrients and natural growth hormones that work together to increase the overall health and size of your plant, resulting in maximum yield. 

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  Supernatural Green Stay 

Supernatural brand Green Stay can be used as a nutrient additive or as a foliar spray to help revive stressed plants. 

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  SuperNova biostimulant 

SuperNova is more than just a seaweed extract! It is a unique blend of seaweed extract (derived from the sea plant Ascophyllum nodosum), specialized amino acids, carbohydrates, vitamin C and B vitamin complex. This enhanced seaweed bio-blend will improve the growth performance of any plant and can be used during any portion of the growing stage. 

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  SUPERthrive 

Add SUPERthrive with your fertilizer for amazing growth! Revitalize ailing plants and trees like magic! Have an over-fertilized problem? SUPERthrive can fix it. 

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  Sweet organic carbohydrate synthesizer 

Botanicare Sweet™ organic carbohydrate synthesizer is scientifically formulated for the bio-synthesis of crucial compounds to maintain optimal metabolism. An ideal formula for vegetables, fruits and flowers. 

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  Technaflora MagiCal 

Fully compatible for use with any quality soluble fertilizer, MagiCal promotes vigorous and healthy plant growth for both soil and soiless gardens with a highly enriched formula of Magnesium, Calcium and Iron. 

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  Technaflora Sugar Daddy 

SugarDaddy is Technaflora's revolutionary new supplement designed to supply essential carbohydrates and all 20 amino acids in a form that plants can readily absorb and utilize. Using this nutrient additive you'll see stronger plant resistance to pests, diseases, frost and drought! 

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  Thrive Alive B-1 Red 

Thrive Alive Red is ideal for both hydroponic and soil applications facilitating vigorous and healthy root development for both cuttings and established root systems. Presoak rooting medium with Thrive Alive Red to reduce transplant shock. 

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  Top Booster 

House & Garden Top Booster is a powerful flowering supplement that triggers early flowering. 

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  Top Shooter 

Wow! Start a new flowering cycle after the regular cycle has stopped by using House & Garden Top Shooter. 

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  Vegetative Growth Booster 

Vegetative Growth Booster is a specially formulated product for vegetative growth. Apply only once during the early growth stage of your plants. 

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  VitaMaxPlus 

Originally designed for use in laboratories and greenhouses, VitaMaxPlus is now available for hobby gardeners. Grotek's VitaMaxPlus is a plant anti-stress formula which includes, calcium, enzymes and amino acids. Created to encourage better root development, larger buds, blooms, fruits and flowers. 

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  VooDoo Juice 

Advanced Nutrients Voodoo Juice is a beneficial bacteria root booster that breaks down old root material into nutritional matter while enabling roots to repair themselves and create new tissue. 

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  White Widow Mycorrhizal Inoculant 

Humboldt Nutrients White Widow is a mycorrhizal powder containing a high amount of many different mycological spores. It is pure endo Mycorrhizal! 

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  Zeus Juice 

Nectar for the Gods Zeus Juice acts as a catalyst to increase the metabolic rate in your plants to help accelerate growth. 

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Misters and Measurers

Angled Measuring Cup - 2 Cup 

OXO has revolutionized measuring liquids with GOOD GRIPS Angled Measuring Cups. The angled surface lets you read the measurement markings by looking straight down into the cup! 

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Angled Measuring Cup - 4 Cup 

The angled surface of a GOOD GRIPS Angled Measuring Cup lets you read the measurement markings by looking straight down into the cup! 

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Big Shot Measuring Glass 

When you need to measure larger amounts of nutrients, or other liquids, turn to Sunlight Supply's Big Shot Measuring Glass! 

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CANNA Spigot 

If you use the 5-liter or 10-liter sized nutrients from Canna, this pour spout can save you lots of effort. 

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Compression Sprayer 

Great for misting water moisture, foliar feed spraying, or applying insecticides, fungicides and other soluable mixtures indoor or outdoors. 

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Giro's bottle mounted sprayer 

Made of high quality brass, Giro's bottle mounted sprayer is designed to screw onto most plastic soda pop or water bottles. 

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Graduated Cylinders - 100 mL 

The 100 mL Graduated Cylinders are imprinted with raised numerals for easy reading. 

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Graduated Cylinders - 250 mL 

These 250 mL translucent Graduated Cylinders are imprinted with raised numbers so they are easy to read. 

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House & Garden Pour Spout 

The House & Garden Pour Spout makes dispensing your nutrients from 5-liter and 10-liter containers easy. 

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International Measure Mug 

The International Measure Mug is a rugged measuring glass that holds up to one pint. 

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Mini Measure 

The Mini Measure is a fast, accurate way to measure small amounts of liquid nutrients or supplements. 

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Mondi Mist N’ Spray 

Ingenius design for a spray bottle! The Mondi Mist N’ Spray has a flexible gooseneck at the nozzle to give you unlimited aiming options. Bend it up, down, sideways or any other way... 

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Nutrient Syringe 

When you need miniscule amounts, the Nutrient Syringe gives you measurements for oz, cc and ml. 

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Portable Commercial Sprayer-Atomizer 

The Commercial Portable Sprayer-Atomizer holds two liquid gallons and weighs about 13 pounds. 

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Precipitator 360° Sprayer 

The Precipitator 360° sprayer can spray up, down, left, right, over and under your garden with a simple twist of the angled nozzle. 

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Pump Dispensers 1 oz 

A great idea for quickly measuring and dispensing small amounts of liquid fertilizers and supplements. 

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Solo One-Hand Sprayer 

Solo's handheld sprayer is a one-hand pressure sprayer with a telescoping wand and a high-quality nozzle that is fully adjustable from direct jet to fine mist. 

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Sunleaves Measuring Glasses 

For best gardening results you need to be accurate with the measurement of plant nutrients. 

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Growco Indoor Garden Supply
1042 Michigan NE  ·  Grand Rapids, Michigan USA  49503-1908
phone: (616) 454-6900  ·  toll free: 877-939-6900
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4hydroponics.com