How about planting in a raised bed?

Zone would help greatly. Mayhaw would work.

Most fruit trees hate wet feet, you have to mound the soil, as high as needed.

Zone would be 1 I think - San Diego coastal. Looking at installing a subdrain at the bottom. It's at the top of a slope, into cut native. I think I created an impermeable basin that the roots just sit in.

Thanks for the advice, going to look into improving the drainage then replanting.

San Diego is a very dry region. I don't think you will have to worry much about poorly draining soil. If anything, all that wet soil will probably help rather than hurt. Just be a little careful when you water, make sure you do not drown the tree in too much water all at once. When it comes to growing fruit trees, the "conventional wisdom/advice" does not always apply in Southern California, which has a very different climate from the rest of the country. At least this is what I have found in my experience.

I live SD coast. I have four trees planted in hard pack clay.

Wash. Navel

satsuma orange

anna Apple

pomegranate

i have no concern for drainage.

I do have a hass avo. I dug three feet deep, amended planting soil.

i then raised the tree about 18" above ground.

Plant whatever you want on a raised mound/bed, the top roots will be able to get oxygen and your tree will be okay... two feet would be good.