girl with tree to plant

Mycorrhizae are beneficial underground fungi that significantly enhance your plant’s root system and therefore its nutrient uptake, establishment in new environments, and overall vitality — naturally.

Here’s a quick primer on three different ways to apply them.

Dry Powders

Dry powders are the simplest way to use mycorrhizae. Microbes will hibernate when conditions get too dry, making the organism very stable and durable. The dry powder can be applied to the planting hole directly to the root system, where it will revive and go to work.

This is the most effective means of applying mycorrhizae. The symbiotic relationship that develops between fungal hyphae and the plant is quick and robust.

For established plantings, there is a different method. Spread the powder under the plant to be treated and lay mulch on top. (Mycorrhizae cannot withstand ultraviolet light, so be sure to have the mulch ready in advance.)

Root Dips

Root dips are another popular method for applying mycorrhizae to the planting zone. In this approach, mycorrhizae are suspended in a superabsorbent gel which glues the mycorrhizae to the roots before planting. Then simply backfill and the mycorrhizae are already in place to begin their amazing work.

Because of requiring contact with the exposed roots, this method obviously isn’t suitable for established trees and shrubs.


For established plants, liquid applications use water to carry microbes down into the soil without digging. Mycorrhizae can be injected into the soil with a root feeder or poured over the top to soak in.

Injection would be preferred for compacted soils as it will deliver the microbes directly to the root zone. If poured on top of the soil, watering is important as dry soil will keep the application on top too long whereas wet soils will soak it up like a sponge.

Keep It Simple

The basics are these:

  • Keep the microbes out of the sunlight.
  • Get the microbes as directly to the root zone as possible.
  • Then nature will do its thing!

How much to use? Look here for Diehard Transplant and here for Diehard Complete.