Kat2

Dig a big hole and fill it with organic matter (which can be whole rotted veggies, leaves, etc. ) before setting your plant. (Ideally your plant is actively growing in a huge pot filled with not sand only.) Top dress with more organic materials. Most of us here in the states use compost or mulch; compost is often preferred because it's already broken down but mulch helps standardize soil temps plus assists in preventing evaporation so both are good. Check out lasagna and hugelkultur gardening as other options.

Once planted, fertilize as needed.

I gardened for years in clay and then for a couple of years in perfect loam. Now I have sand. It's different but doable. Well, maybe not for tomatoes but I do have bananas growing fine here.

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