Sow or Plant
In the beginning of January; sow Asparagus seeds indoors in trays. Sow Asparagus in seedling trays in soil that is between 75-80o F at ¼- ½” depth. It will take about 3-4 weeks to germinate. Starting indoors ensures good germination.
Another option is to plant Asparagus 1 year old crowns. In January, not in a hot bed, dig a 12” x 12” hole and in the center of the hole, hill 3” of compost at the bottom. Place each crown with the roots down (they are the long part) and the crown up; spread the roots out evenly. Space each crown 18” apart. Cover the crowns with 2”-3” of soil, adding more soil throughout the year until the hole has been filled.
Transplant the seedlings into garden in June for harvesting two years from now. The pH range should be between 6.5-7.5. Plant the Asparagus in rows giving 18” spacing between each seedling or crown and 6” between each row. Fertilize with compost tea each week in the spring, summer and fall. In the spring, the spears grow directly out of the ground. As spring turns into summer, a brushy fern grows. Each winter, after the ferns have completely died back but before snow fall, cut back the Asparagus fern and then spread and inch of compost or rotted manure over the Asparagus bed and mulch with 6” of straw.
Harvest Asparagus spears the 3rd year after transplanting the seedlings and the 2nd year after planting the crowns. Wait until the spears are at least 1 cm in diameter and from 6 to 8 inches in height. Harvest lasts for 6-8 weeks and typically occurs when you are harvesting your peas. Bend and break to harvest your spears. Stop harvesting when spears become stringy and the tips begin to loosen and open.
Collecting seeds hardly seems necessary for asparagus since each crown will continue to grow spears for 15 years or more; but in the interest of sustainability, here we go.
Asparagus crowns are either male or female. There are some new hybrid varieties which are all male with thick stalks — these you cannot collect seeds from. The male crowns produce mass quantities of thin spears and produce pollen and the female crowns produce fewer, thick spears and berries. (Please note: what also influences the thickness of the spear is the age of the crown. As time progresses, spears become thicker.) Asparagus is insect-pollinated. The fruit is a small red berry which is produced by the female plant. When they start to dry, cut a few of the ferns with berries and allow them to dry for 5-7 days in paper bags in a dry, sunny area. Keep the majority of the ferns, allowing them to die back naturally, male and female to ensure that your yearly Asparagus crop flourishes. Remove the berries. Soak the berries until the coating comes off and then dry on paper towels for 5-7 days.