Asparagus are unique among vegetables because they are perennials, so the same plants come back up in the garden year after year; their sprouts are the edible part of the plant. It takes at least two seasons after planting asparagus to harvest any of the sprouts, but when they are planted, they will come back up in the same spot for up to 30 years. Asparagus is a hardy plant in most areas of the country, with the exception of the warmest zones, due to mild winters that do not allow the plants to go dormant.
Asparagus requires well-drained soil in a sunny location. When planting a bed of asparagus, the plants should be spaced around 12 to 18 inches apart, and all weeds should be removed prior to planting. Begin preparing the soil for asparagus in the fall, adding around 3 inches of organic matter to each row and tilling it in. Soil should have a pH of less than 6, and soil can be adjusted by using lime or other nutrients.
Cut new shoots from asparagus in the spring when they reach around 8 inches in height, snapping the shoots off at the soil line. Harvesting every other day ensures that the asparagus doesn't get too tough to eat.