Answer: It's hard to say exactly what happened to your tomatoes. If other plants in your vegetable garden grew well, and just the tomatoes were affected, I would suspect an insect or disease problem. If all the plants in the garden did poorly, I would suspect environmental factors. Did the trees shade the garden? Tomatoes require full sun--at least 6 hours per day but preferably more. How is your soil? Poor soil that is low in nutrients and/or too acid or alkaline will affect plant growth. Drought and/or excessive water can also lead to stunted plants.
I would try growing disease-resistant varieties, be sure they get plenty of sun and adequate, consistant water, and mulch them with straw. If you haven't done so, I suggest you have a soil test done to determine your soil's nutrient levels and pH. Your county Cooperative Extension office should offer soil test kits at a reasonable price.
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