Sandy soils, hmmm good drainage!

Too good, moisture and nutrients zoom through sandy soils! Hmmm need to build sandy soil up to retain moisture and nutrients.

How to do that?

Dig in LOTS of organic material: lawn clippings, vege scraps, bought compost, whatever. You can use “water retention crystals” or similar, just keep adding organic crap (dig it in else you invite rats.) Cover crops incl clover are also good.

Keep digging in organic crap. Lawn clippings, vege scraps, clover and other cover crops, bought compost.

Test your soil—pH? You want a pH of 6.5–7 generally for veges.

Plant a crop, plant cover crops to prevent rain/watering to flush nutrients way down out of reach of roots of crop plants.

Kaolin clay which when blended in the right quantities gives amazing results...

https://www.soilsolver.com.au/post/soil-amendments-sandy-soils

Yeah, but don’t add sand to clay soils—creates cement instead of loam!  :D ;D