200 m2 square farm in Cochabamba, Bolivia, zone 8

I’ve had the place for a year and have had general success planting cucumbers, beetroot, carrots, radishes and tomatoes. Now I am trying to figure out a plan to repair the soil. The land is on a slight angle with a depression at the bottom next to the neighbours wall. Already I have alfalfa on one of the slopes and I plan to put citrus trees and lavender on the other. At the bottom of the slope I’m not sure. Right now I’m growing cabbages there and they are doing reasonably well but I wish they were growing faster.

I also have a small plot in half shade underneath a Molle tree. The beets are bolting and the pumpkins seem so-so but the carrots are doing very well.

In this dip of the land it seems always more or less green. What is good to plant there? Anything in particular?

Is lavender and citrus trees a good idea for the slope?

What are some great plants for zone8?

I am heavily mulching everything now, and making as much compost as I can with the alfalfa to repair the soil.

Thanks for reading, any advice is appreciated.

(Pictures are a little old but give general idea)