Answer: Three words: compost, compost and compost! Sandy soil holds very little water and nutrients. Organic matter is the best solution for such a soil problem. You can purchase compost by the yard to get a head start.
I would begin by mixing about 4 inches of compost into the surface 4-6 inches of soil. Then you can mulch the garden with leaves, and rototill the partly decomposed leaves in at the end of the gardening season.
Good luck and thanks for the question!
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