Succession planting for three-season harvest

The most effective season extension is not a physical structure but a planting strategy: using succession planting to fill the bed with productive crops from the earliest possible spring date through late fall. A three-season plan for a single 4x8 bed in zone 6 might look like this. Early spring (March): plant peas, lettuce, radishes, spinach under row cover. Late spring (May): when peas finish, replace with tomatoes, peppers, beans, and basil. Late summer (August): as bush beans finish, replace with fall lettuce, kale, carrots, and beets. Late fall (October): cover remaining crops with a cold frame for winter harvest. This approach produces 4 distinct harvests from one bed in a single year. The key tools are: knowledge of your frost dates, a planting calendar (free from your county extension service), and the discipline to pull finished crops promptly and replant immediately. Every day a bed sits empty is lost production. Keep transplants ready in cell packs or pots so you can plug them into empty spaces the same day you clear a finished crop. Combining succession planting with physical protection (cold frames, row covers) achieves maximum season length.