Asparagus is a member of the lily family. It grows best from crowns, though a few can grow well from the seed of open-pollinated varieties like ‘Purple Passion’ and ‘Martha Washington’.
If growing from seed, start them under grow lights in mid-January. Once plants are 8” – 12” inches tall, harden them off outdoors for a week before planting in their permanent location. Asparagus has both a male plant and a female plant. You can see which ones are female in the fall, because they make seed pods or little red berries. You may want to remove the female plants because they hardly produce any spears and their berries are toxic.
Growing from crowns rather than seed will produce a larger plant much faster. Root clusters or ‘crowns’ look very much like a spider with a head and legs! Creepy cool! When purchasing crowns, look to see if there is new growth in the form of tiny white or green buds. You’ll see these growing from the ‘head’ of the root. Just as in potatoes, these sprouts are called ‘eyes’. Halloween in springtime!
Whether crowns or seeds, expect asparagus to take a little time before it is ready to eat. Depending on your soil, it will be 2 to 3 years before your first harvest. Growing asparagus in raised beds will help reduce the invasion of weeds and grasses. Mulching well will help with this too. Make sure the soil drains well because asparagus hates wet feet!
Once hardened off, they are ready to plant. Dig a ditch about 12 inches deep. At the bottom of the ditch, make a little hill! Each crown sits like a spider straddling the hill. In other words, the roots lay over the soil with their ‘eyes to the sky’ and their legs draped over the hill. If you have sandy soil, bury the crowns so the eyes are about 6 inches deep. If your soil is heavier, plant the crowns so their eyes are shallower, about 4 inches. Cover with soil and compost and feed with organic fertilizer.Use a low dose organic fertilizer, like 5-5-5 or 2-5-3. Using a high nitrogen fertilizer will not grow more spears! If planted too deep, your asparagus will grow fat spears and less of them. If planted too close to the surface, you’ll have a lot of spears but they will be too thin!
As the eyes start to grow, cover them again with 2 more inches of compost. They are heavy feeders. DO NOT harvest anything the first year. This will allow the plant to establish itself to survive the winter. The following year you can start harvesting, but only cut the emerging spears in their first month of growth. Every spear that comes up afterwards should be left so the plant can produce its ferny leaves for energy to make next year’s crop!
Photo by Stephanie Studer