Is Miracle-Gro too strong for your average Bonsai tree?

It probably depends on what kind of plant the bonsai is. Look up the plant and see what type of fertilizer they recommend for it. If you do miracle grow, I would use it in the strength they recommend for the plant and only when they say to use it on your particular plant, it may be different from the recommendations on the miracle grow container. Miracle grow is a good multipurpose fertilizer, but can be strong for some plants and the timing on the package could be more frequent than the plant needs for healthy growth.

Bonsai Soil. The soil you will need for a bonsai tree depends on the variety of tree you are trying to grow. ... Fertilize regularly; bonsai shaping is easiest done with consistent growth. Use a liquid fertilizer solution like Miracle-Gro mixed with water every two to four weeks during the growing season.

https://www.bonsaiempire.com/forum/repotting-and-soil/1167-miracle-gro

What kind of Bonsai is it? Bonsai trees can be any plant it's an art form Bonsai: An Elevated Art Form. The art form of bonsai (盆栽) has been a Japanese tradition for centuries. ... The word bonsai was derived from the Japanese pronunciation of the Chinese term for the art, penzai. Bon is a tray-like pot typically used for bonsai culture and sai means to plant. All plants are different some need a little more,a little less,minerals,special nutrients than others. Miracle grow water soluble is ok for just about any plant but as I said some plants may need a little extra.