Mound planting, even in soil with good drainage, is good for avocados.
Check this great information on growing backyard avocados in these videos.
https://youtu.be/rX9pwyFb1rU
Basically, you’ll need a lot of dirt more than you think, to make a mound. Place your avocado out of the pot, on bare ground and rake your dirt up to the level of the original soil in the pot so the trunk is emerging from the top of a gentle mound. If you want to add aged
compost, spread that on the mound dirt, before covering with
wood chip mulch and pretty much pile it as deep as you can, 12” deep will breakdown into about 1” in a year. Keep that mound moist. You solve a lot of problems ahead of time by mound planting.