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Companion Liquid Biological Fungicide
Multi-Purpose Fungicide

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• Prevent and Control Fungal and Bacterial Diseases
• Build Denser Strong Root System
• Activates Induced Systemic Resistance (ISR)
• Stop Damping Off of Seedlings
• Increase Stock Mass on Plants
• Naturally Occurring Bacillus subtilis GB03
Bacillus subtilis GB03* .
Other Ingredients:
*Not less than 5.5 X 1010 Colony Forming Units (CFU) per gallon
Total Nitrogen (N)
2% Water Soluble Nitrogen
Available Phosphate (P2O5)
Soluble Potash (K20)
Calcium (Ca)
Magnesium (Mg)
Derived From: Concentrate fermented plant extracts, iron glucoheptonate
Companion® is a broad spectrum Biological Fungicide for the prevention, control and suppression of soil borne and foliar fungal and bacterial diseases. It can be used throughout the growing season on all types of crops to control diseases such as Phytophthora, Fusarium, Pythium, Sclerotinia, and on foliar diseases such as Alternaria, Botrytis cinerea, Colletotrichum graminicola and Xanthomonas.
It contains a natural rhizosphere bacteria that quickly populates the soil, forming protective colonies on and around delicate root hairs and on the leaf surface, destroying and warding off diseases. It is a gram-positive bacterium, which survives in extreme environmental conditions including heat & drought, making it a durable and reliable fungicide growers can trust.
This unique biological has been studied for years at leading universities and is proven to elicit the plants natural defense resistance (ISR), to fight against many pathogens. Companion can be used in combination with other fungicides and phosphites (PO3) at reduced label rates, boosting their efficacy, resulting in higher yields and a more marketable crop. Companion can be used up until harvest and has an REI of 4 hours. Companion is natural rhizosphere microorganism that contains high concentrations of organic components that can neutralize and reduce the harmful effects of TDS (Total Dissolved Solids) buildup from repeated applications of both chemicals and high salt fertilizers.
Unlike synthetic fungicides that target a specific protein synthesis or the cell membrane, Companion® Biological Fungicide has multiple modes of action involved in its biocontrol performance to fight pathogens. It combines four modes of action to suppress diseases:
1.GB03 strain of Bacillus subtilis produces a broad spectrum antibiotic, Iturin, an antifungal /antibacterial lipopeptide that destroys pathogens by puncturing their cell walls so that the pathogen desiccates. When used in conjunction with synthetic fungicides, Companion improves their efficacy by allowing them to easily move into the cell.
2.Bacillus subtilis GB03 produces unique metabolites (lipoproteins) that have antagonistic activity against pathogens inhibiting their protein production.
3.Companion activates the plant’s natural defenses, Induced Systemic Resistance (ISR), allowing the plant’s immune system to ward off disease and reduce its susceptibility to pathogen attack.
4.Unlike traditional fungicides which often stunt plant growth, Companion actually promotes plant vigor. It is a beneficial Rhizobacteria (PGPR) that produces auxin-like hormones. It quickly colonizes on roots forming a biofilm that produces surfactins, improving nutrient uptake, increasing root growth, enhancing lateral branching, and promoting overall vigor and yield, in a wide variety of crops.
There is a unique advantage in incorporating Companion® Biological Fungicide into your growing program. The active ingredient in Companion is Bacillus subtilis GB03, well known as Plant Growth Promoting Rhizosphere (PGPR) bacteria. Not only is it antagonistic to soil-borne pathogens, but interact with plants improving growth. Highly efficient in root colonization, GB03 produces growth metabolites such as auxin compounds which improve plant vitality by enhancing root elongation and branching, maintaining root health, water uptake, improving nutrient uptake such as phosphate solubilization, iron availability and increase the plant’s ability to resist environmental stress. Unlike chemical pesticides, Companion promotes overall growth, resulting in better development and flowering.
Green algae, called cyanobacteria, is a nuisance that can cause negative impact in hydroponic systems. Bacillus subtilis GB03 has the ability of inhibiting or biodegrading cyanobacteria by destroying its cell and plasma membranes, releasing cell organelles. This is an effective and environmentally friendly option for control versus chemical methods such as Algaecides.
Companion Biological Fungicide meets the criteria set by the Washington State Department of Agriculture (WSDA) under I- 502/I-692 for use in the production of Marijuana in Washington State. The Colorado Department of Agriculture has determined under Title 35, Article 10, Section 117 of the Pesticide Applicator’s Act, that Companion Biological Fungicide may be used in the following cannabis production scenarios: Commercial Marijuana Production and Marijuana for Personal Use.
Companion can be used alone or in combination with traditional chemical fungicides either in a tank mix or rotational program. Its multiple modes of action help prevent pathogen resistance. This makes Companion® an ideal foundation for an effective Integrated Pest Management (IPM) Program.
Companion Biological Fungicide can be used on all potting soils such as peat, bark, and perlite combinations, or applied as a drench on potted plants, outdoor field crops, and indoor potted plants. It can be used on all stages of growth including, seed germination, cuttings, potting, plug, sizing up and field applications. It can be applied both as a foliar spray, or soil drench to control fungal disease. DO NOT tank mix with copper products, highly caustic or acid materials. Do NOT mix concentrates together. Always fill tank ¾ full with water before adding concentrates. It can be tank mixed with other technical materials, organic products or fertilizers. It is effective on all types of growing media including bark-containing mixes. It can be incorporated along with starter fertilizers to enhance their efficacy. Companion is a preventative fungicide. For best results begin applying Companion from the beginning of the crop cycle or prior to the onset of any diseases. Botrytis cinerea (Bud Rot) affects many crops and is prevalent in nature. To prevent Bud Rot be sure to thoroughly wet stems, buds and leaves to the point of run-off with a solution of Companion. Remove infected leaves and buds. Companion can be used up to the day of harvest.
Companion Biological Fungicide should be stored in normal warehouse conditions. Keep in a cool dry location that does not go above 100o F for long periods of time and keep out of direct sun light. Do not store below 32o F. Companion Biological Fungicide has a neutral pH. Always store in original container and keep tightly sealed after opening. Refer to SDS for additional information on storage, handling, safety, disposal and shipping.

Companion Liquid
Biological Fungicide

Seedlings and Clones



Transition and Early Bloom

Full Bloom


No. of Weeks






Hours of Light







Soil & Soilless Mixes

6 ml

10 ml

5 ml

5 ml

5 ml


6 ml

10 ml

5 ml

5 ml

5 ml


.25 ml

1 ml

5 ml

5 ml

5 ml

Apply weekly, amounts listed are to be added per 1 US Gallon (3.79 liters)

Application Recommendations



Frequency / Notes

All Strains of Plants Grown in Soil or Soilless Mixes Indoors and Outdoors

Mix 5 - 10 ml per gallon water.

Begin applications at time of transplanting or seeding. Apply weekly throughout growing cycle.

Foliar Applications: Mix 5 - 10 ml per gallon water.

Begin applications at time of transplanting or seeding. Apply weekly throughout growing cycle. Spray until run-off.

Hydroponics and Constant Feed

Charging: 5-10 ml per gallon of water

Add whenever nutrient solution reservoir is changed. Replenish every 7-10 days or when water is changed.

Seeding Disease Protection

Mix 6 ml per gallon of

Drench seed trays until thoroughly soaked at timeof seeding. Repeat in 7-14 days.

Clones Disease Protection

Mix 6 ml per gallon of water.

Thoroughly drench rockwool, or root cubes before sticking cutting. Also, drench trays of cutting with solution of Companion after planting. Repeat in 7-10 days.

Sizing-Up & Transplanting

Mix 10 ml per gallon of water.

After planting in new container, thoroughly drench plant with diluted Companion.

Prevent Bud Rot Caused by Botrytis Cinerea or Gray Mold

Mix .25 - 5 ml per gallon of water.

Spray foliar applications weekly throughout entire flowering phase and up to harvest. Spray until run-off