Understand Sun, Soil, Water, and Easy Plants
Plants need 6-8 hours of direct sun daily (leafy greens need 6, fruits/veggies 8). Test soil pH (ideal 6.0-7.2) using a kit from extension services. Water 1 inch/week at soil level. Start with easy crops: radishes (21 days), lettuce, beans, cherry tomatoes, carrots.
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Note your climate zone and season.