Question: Can you give me some information on growing asparagus?
Answer: Homegrown asparagus is one of the earliest vegetables of the spring. Asparagus is one of the best vegetables you can grow at home because it’s very healthy, extremely versatile and fairly simple to grow. Its quality is much better than store-bought spears, and it is less expensive. Once established, a well-prepared garden patch can last for decades.
Formerly of the lily family, asparagus is now in a family all of its own called Asparagaceae. Known botanically as Asparagus officinalis, it is native to the seacoasts of Europe, North Africa and Asia.
Nutritionally, asparagus is low in calories and sodium but high in folate and is a significant source of such vitamins and minerals like potassium, thiamin, vitamin C and B6. Since it is a vegetable, it is a good source of fiber as well.
Careful attention should be given to your site selection because asparagus will occupy the land for 10 years or longer. Asparagus needs eight hours of sun per day. Asparagus is a long-lived perennial, so do not plant it where trees or tall shrubs might eventually shade the plants or compete for nutrients and water. Select a site that is well drained and fertile. The pH should be around 6-7. A general recommendation is to add a well-balanced fertilizer before planting.
Although asparagus can be established by direct seeding or transplanting of greenhouse grown seedlings, most home gardeners prefer planting field grown one-year-old crowns. October through March is the best time for planting transplants or crowns.
Dig holes or trenches about 8 inches deep and 10 inches wide. Spread the roots in the bottom of the hole or trench and cover the crowns with a 2-inch layer of sifted compost. Even though the young crown will appear to be a lifeless mass of stringy roots, it will begin to send up small green shoots (spears) shortly after planting.
During the summer of the first year as your asparagus grows, the trench should be slowly filled with a mixture of fine topsoil and compost. It is advisable not to do the filling too rapidly or the growing plants will likely be stifled. The tops of the crowns should be 6 inches below the soil surface when the trenches are completely filled. This allows for cultivation and also provides a sufficient depth of soil for new buds to develop on the top of the crowns. Keep your plants well-watered.
Weeds are the most common problem in asparagus plantings because they compete with the crop and reduce productivity. To manage annual weeds, mulch with straw, grass clippings, chopped leaves or conifer needles after the trenches have been filled in.
The asparagus plant is made up of the top (spears turning into ferns), the crown (buds) and the roots. All three are vital to a productive plant. The ferns are the “factory” which, through the process of photosynthesis, produces food stored in the crown and roots below ground. The number of vigorous spears in the spring depends upon the amount of food produced and stored in the crown during the preceding summer.
Producing a good crop of ferns is necessary to ensure a good crop of spears the next spring. Do not cut back the old ferns until the end of the season when they are completely dead. In the fall, nutrients move from the dying ferns to the crown. Removing the ferns too early weakens the crown and may thereby reduce the size of the spears the following spring.
But what if you wanted to grow asparagus in pots? Can it be done? The answer is yes, you most certainly can grow asparagus in a large deep pot. Maybe you don’t have enough space in your garden anymore, or maybe you live in an apartment — whatever the reason, growing asparagus in pots or containers is easy. Just follow the steps outlined above.
Harvest your asparagus two or three years after planting the crown. Cut off spears at the ground level with a sharp knife. Only harvest the spears once in their second year. After giving your asparagus time to establish, you can harvest the spears in the following years from early spring when the spears reach about 8 inches long for about eight to 10 weeks.
Selected varieties that will perform well in our area: Jersey Knight is one that does well in heavier soils. Pacific Purple bears dusky plum-colored stalks. They usually turn green when cooked. Jersey Supreme is an all-male variety, which makes it a high-yield asparagus. Female asparagus plants produce thinner spears than male plants, though both are equally tender when cooked.
What’s great about asparagus is that it’s a hardy perennial that will keep on producing for up to 20 years, so once planted and well taken care of, your asparagus plant can actually keep on giving year after year.