I've been very happy using the Plant Success brand of mycorrhizal fungi
in granular form or gel form for transplants. I use it with every fruit
tree. I give a lot of credit to it for growing healthy tomatoes and
strawberries. I'm not a believer in the more expensive tablet form or in
spraying mycorrhizal fungi on the soil. It's supposed to come in
contact with the root surface.
I'm also not fond of buying other ingredients which have been added to
mycorrhizal fungi (humic acids, vitamins, or kelp) which I can always
add on my own if I so choose and thereby know the source.
Mucho information at the toll free number on this web site.