Research Report
Companion® Biological Fungicide Goes Above and Beyond Chemical Fungicides
What is Companion®?
A broad-spectrum biological fungicide for soil-borne and foliar diseases
Companion's GB03 strain of Bacillus subtilis has multiple modes of action to prevent and control plant diseases. It produces a broad-spectrum Iturin antibiotic that disrupts the cell-wall formation of pathogens, and it triggers an advantageous Induced Systemic Resistance (ISR) in plants, whereby a plant's natural immune system is activated to fight plant diseases. Companion's fast-colonizing beneficial rhizobacteria stimulate root growth and promote turf vigor while also crowding out plant pathogens. Easy to use and handle, Companion is an environmentally-friendly fungicide with an unsurpassed safety profile and a low 0-4 hours REI. Because its modes of action circumvent the development of pathogen resistance and since it can be used alone or in combination with traditional chemical fungicides, Companion is the ideal foundation for an effective integrated pest management and disease management program.
  • Companion® was the first-ever EPA registered liquid biofungicide on the U.S. market
  • Over 15 years of university testing
  • Researched at over 30 accredited institutions across the country and around the globe
  • Registered and approved for use in over 25 countries
greens devestated by Pythium
Hawaii greens with Pythium
The greens at this prestigious golf course in Hawaii were devastated by Pythium Root Rot. In large areas, over 50% of the turf was
brown and dead.
The roots were largely killed off as well, with less than ½" of root growth. It was so bad, the turfgrass could be peeled up like paper.
New root growth
Healthy golf course
One month after the first application of Companion®, the turf in its recovery period. Most dramatic is the 3" of new root growth that developed after 30 days.
The "Happy Ending": The beautiful and healthy golf course as it is today.
Turf & Ornamental Disease List:
(Colletotrichum graminicola)
Brown Patch
(Rhizoctonia spp.)
Dollar Spot
Summer Patch
(Magnaporthe poae)
Fusarium Patch
(Fusarium nivale)
Pythium Blight
Pythium Root Rot
Pythium Crown Rot
(Pythium spp.)
Stem & Root Rot

Break-Through Technology

Growth Products' pioneering research in environmentally safe solutions for the Green Industry led to Companion®'s technology.

Years of research went into developing Companion and gaining its EPA registration in every green industry market including Turf, Landscape, Greenhouse, Nursery, Ornamentals, Hydroponics, Agriculture, and Home & Garden Use. Companion has been tested at leading universities, by government agencies, and by the most prestigious golf courses around the world.

Rhizoctonia, Fusarium, Gaeumannomyces graminis (Take-All patch), Helminthosporium, and ERI fungi were just a few of the problems plaguing The Villa in Queensland, Australia.
The superintendent began using Companion®, tank-mixing it and rotating it with several chemical fungicides including Chlorothalonil, Iprodine, Triadimenol and Thiram.
With the help of Companion, The Villa is now disease-free. The superintendent recently emailed that "The worst green on the course has not had any disease for 14 months, which we still can't believe."

Multiple Modes of Action

To prevent & control turf diseases and to improve turf vigor

  • Directly competes against soil-borne pathogens by quickly colonizing a plant's root hairs with beneficial bacteria, thereby crowding out disease-producing microbes and creating a "shield" to protect plants.
  • Produces strong Iturin antibiotics that kill pathogens by disrupting cell wall formation.
  • Creates a highly beneficial Induced Systemic Resistance (ISR) by stimulating the plant's phytohormones and natural immune system to better resist diseases.
  • Acts as a Plant Growth Promoting Rhizobacterium (PGPR) that stimulates better rooting and better overall growth.
  • Is an important tool in a turf manager's Disease Resistance Management Program, helping to prevent pathogens from building a resistance to chemical fungicides.
  • Is non-selective to plant materials, and thus is beneficial to turf, woody ornamentals, trees, perennials, annuals and virtually all crops.
  • Contains gram-positive bacteria which survive in even extreme environmental conditions including heat and drought, making it a durable and reliable fungicide that turf managers can trust.
Bacillus subtilis spores populating the root hairs
Notice hyphae formation around root hair providing a protective glove

Cultural Management

As a 100% natural and organic biological fungicide, Companion® is an important tool in a turf manager's Integrated Pest Management (IPM) Program. Prevent resistant pathogens that often occurs with chemical fungicide products. Companion's multiple and unique modes of action inhibit the pathogen's ability to develop resistance.

To prevent & control turf and landscape disease and to improve turf vigor, apply Companion Biological Fungicide throughout the growing season on all types of soils, turfgrass and ornamental varieties. Apply when ground temperatures have reached 45 degrees F (7 degrees C) or above, and until late fall prior to first frost.

Easy to use, store, and handle, Companion can be tank-mixed with most fertilizers, micronutrients, wetting agents, organics, contact fungicides and systemic fungicides to save on time and application costs.

Other benefits include:

  • Low 0 - 4 hour REI for workers.
  • No special storage requirements; remains shelf stable for more than two years.
  • 100% miscible in water and may be applied through all types of irrigation systems.

Rutger's Field Day

Summer Patch (Magnaporthe Poae)
Kentucky Bluegrass
This photo is the untreated control showing Summer Patch (Magnaporthe poae) damage.
This shows the results of applying Companion® at 4 oz. every 14 days.

BROWN PATCH (Rhizoctonia)
Colonial Bentgrass
This untreated control shows damage by Brown Patch (Rhizoctonia) at the Rutgers' Field Day, New Brunswick, NJ.
Here, Companion® has been applied at 4 oz. per 1,000 square feet every 14 days, and Daconil® Ultrex has been applied at 3.8 oz.

Make Fungicides More Powerful With Companion®

Companion® excels as a stand-alone biological fungicide and as a beneficial "companion" fungicide. Companion increases efficacy when tank-mixed with chemical fungicides, or used in rotation with other fungicides, thereby reducing your total chemical costs, and helps prevent the development of disease resistance.

Companion has been tested and proven effective with:

  • Daconil®
  • Bayleton®
  • Heritage®
  • Cleary's 3336™
  • Chipco®
  • Subdue®
  • Banner Maxx®

Daconil®, Heritage®, Banner Maxx®, Subdue® are registered trademarks of the Syngenta Group Company. Chipco and Bayleton are a trademarks of Bayer AG. Cleary's 3336 is a trademark of The Cleary Corporation. Companion® is a registered trademark of Growth Products, Ltd.


  • Clearly visible abundant new root growth
  • Improves quality of turf stand and turgidity
  • Increases hyphae formation
  • Reduces thatch
  • Mineralizes soil
  • Improves tillering
  • Enhances nutrient uptake
  • Eliminates black layer
  • Stops Bermuda and Poa decline
  • Is antagonistic to blue-green algae (Cyanobacteria)
  • Helps reduce salinity in problem soils
  • Speeds germination during divot repair
  • Improves drought tolerance