Asparagus is a true perennial. Commercial growers usually count on 15 to 20 years of harvest; home gardeners can keep theirs going for 40 years or more. This means you must be very thoughtful about where you plant it. Asparagus seeds grow plants with deep root systems. If you're only growing a few plants — two or three asparagus plants are probably enough for a family, then consider growing them at the edge of the vegetable patch or even as a perennial border. The long, branching, green stems and delicate, airy foliage form tall, (to 150cm) attractive plants that will add height and volume to the back of the border. If you want to get a jump on the season, consider planting asparagus crowns.