Mycorrhizal fungi occur naturally in most undisturbed soils; but I would think not in container mixes; so if you think they are beneficial... and I do... why not add them.

Johnmerr Thanks for getting back on this. I'll go ahead and try some on 2 of 4 sweet lee tangerine trees

Citrus planted in situ are quite dependant upon their mycorrhizal relationship with specific soil borne fungi. But it is a specific interrelationship and will only occur if the appropriate fungal inoculents are available. Citrus make arbuscular mycorrhizae within the actual fine roots (root hairs).

The response to inoculation in containers is highly variable, even if the correct fungal propagules are integrated into the mix. Too much can be bad. One has to be careful to use appropriate fertilizers.

In containers, where the nutrient and water supply depends upon humans and the entire root system is held hostage, so to speak, the benefits might be obscure. Increased heat, cold, and drought tolerances might be noticeable.

The bottom line.....research the inoculant before buying. One size does not fit all. And do not use the product like a fertilizer nor should you expect the same results.

Most experts would say that mycorrhizal relationships are essential to good citrus production....when planted in the ground. This would be especially so in over worked, over fertilized, over drenched or sprayed soils. Some fertilizers, fungicides, herbicides, and insecticides damage beneficial soil microoganisms, including the types of fungi that may form mycorrhizae.