Mycorrhizal Fungi for Trees
Mycorrhizal fungi for trees that extend the root system underground. Add at planting for faster establishment and tougher, healthier trees.
Apply it around the root zone or into growing media as directed to make beneficial biology an easy part of planting, repotting, or routine garden care.
Why You'll Love It
- Root Partnership Fungi that extend a tree's root system further underground.
- Transplant Support Add it at planting, when a young tree is establishing roots.
- Nutrient Uptake A wider root network reaches more soil water and nutrients.
Made by growers
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- Made in-house, in the USA. Every bottle mixed and filled by us, not a third party.
- We're growers, not resellers. We use this on our own plants before it ships.
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Mycorrhizal fungi for trees that extend the root system underground. Add at planting for faster establishment and tougher, healthier trees.
How to Use Mycorrhizal Fungi for Trees
| Method | Amount | How Often |
|---|---|---|
| Transplanting | Sprinkle on the roots and in the hole when transplanting | Once, at planting |
| New soil prep | Mix in 4 Tbs per cubic foot of soil | Once, when preparing soil |
| Established trees & shrubs — small (spring & summer) | 1/2 to 1 tsp, spread evenly around the trunk and gently mixed into the top of the soil, then watered | Apply every 2-4 weeks |
| Established trees & shrubs — medium (spring & summer) | 1 to 2 tsp, same application | Apply every 2-4 weeks |
| Established trees & shrubs — large (spring & summer) | 1 to 1.5 Tbs, same application | Apply every 2-4 weeks |
| Established trees & shrubs (fall & winter) | Same amounts | Apply every 4-8 weeks |
| Compost tea | 1/4 - 1/2 tsp per gallon of compost tea | Add when brewing |
This is a dry inoculant, not a fertilizer — the goal is contact between the granules and the roots or soil. The planting hole is where it earns its keep; on established trees, apply out toward the drip line where the feeder roots are, not against the trunk.
What's Inside
Three groups of living organisms, measured in colony-forming units rather than NPK — and the fungal lineup is deliberately two-sided. Ectomycorrhizae (Pisolithus tinctorius at 106 million cfu per pound, plus five Rhizopogon species) sheath the roots of oaks, pines, spruces, firs, and other conifers and hardwoods. Endomycorrhizae (Rhizophagus intraradices) colonize maples, fruit trees, dogwoods, magnolias, and most other landscape trees from within the root. Whichever type your tree partners with, its fungi are in the bag, extending the root system's reach for water, phosphorus, and micronutrients.
Backing the fungi, a bench of soil bacteria — Bacillus subtilis and five other Bacillus and Paenibacillus species at 580-680 million cfu per pound each, plus two Streptomyces — improves nutrient cycling in the root zone, and two Trichoderma species help beneficial organisms dominate the soil around the roots. There's no NPK by design: this rebuilds the underground partnership forest trees get for free and landscape trees usually lack.
Made For
Landscape and yard trees at planting or established — oaks, maples, pines, spruces, evergreens, dogwoods, magnolias, crepe myrtles, Japanese maples, and fruit trees — plus shrubs, balled-and-burlapped stock, bare-root plantings, and trees struggling in compacted or builder-grade soil.
Problems It Solves
- Newly planted trees that sit stalled for a year instead of establishing
- Transplant shock in balled-and-burlapped or bare-root stock
- Trees in compacted or builder-grade soil that barely grow
- Established trees that respond weakly to fertilizing and watering
FAQs
How do I apply mycorrhizal fungi to trees?
At planting, sprinkle it directly on the root ball and into the hole — direct root contact is the highest-value application. For new soil, mix 4 Tbs per cubic foot. For established trees, spread 1/2 tsp to 1.5 Tbs by size around the trunk out toward the drip line, mix into the topsoil, and water — every 2-4 weeks in spring and summer, every 4-8 weeks in fall and winter.
Does this work on my kind of tree?
Almost certainly, because it carries both fungal types. Oaks, pines, spruces, firs, birches, and beeches partner with ectomycorrhizae; maples, fruit trees, dogwoods, magnolias, crepe myrtles, and most other landscape trees partner with endomycorrhizae. Both groups are in the blend at labeled counts, so the right partner is present whichever family your tree belongs to.
What do mycorrhizae actually do for a tree?
They colonize the roots and grow outward as a network of fine threads that functions as an extension of the root system — in forests, most trees run on this partnership, reaching water and phosphorus far beyond their own roots. Landscape trees planted into disturbed or builder-grade soil often lack these fungi entirely. Inoculating restores the partnership, which is why planted-with trees establish noticeably faster.
Do I still need tree fertilizer?
Yes — this contains no NPK. The fungi and bacteria improve how completely roots capture water and nutrients, but they don't supply nutrition. The pairing works in both directions: fertilizer without biology leaches past sparse roots, and biology without nutrients has less to deliver. Run it alongside a tree fertilizer, especially for young trees putting on structural growth.
Can this help a mature tree that's declining?
It can be part of the answer, not the whole one. Decline in mature trees usually has a primary cause — compacted soil, grade changes, trunk damage, drought stress, or disease — worth diagnosing first, and a struggling mature tree merits an arborist's look. Where the inoculant helps is rebuilding root-zone biology in compacted or disturbed soil, applied at the drip line where the feeder roots live.
When will I see results?
Trees run on the longest clock in the yard. Colonization takes several weeks after root contact; visible evidence follows seasonally, not weekly. Transplants show it first — less dieback, earlier bud break, and steadier first-season growth. On established trees, expect the difference across a full growing season: better leaf color and density, improved drought tolerance, stronger response to feeding.
Related Products
Root Stimulator for Trees Tree And Shrub Fertilizer 10-10-10 for Trees