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Hello Mid-Ohio Valley gardeners and farmers! Spring has definitely arrived in the valley as we have seen warm temperatures and plenty of moisture, and hopefully experienced the last frost until fall.

This week I want to talk about a great perennial vegetable for the garden, asparagus (Asparagus officinalis). It is a member of the onion family of vegetables and can yield for 10 or more years. It is a great choice for the home gardener or small farms selling at local markets. Asparagus produces good yields, has many health benefits, comes back year after year and is one of the first crops harvested every spring.

Asparagus has a rich history. It thrived in the wild and was first domesticated by the Macedonians about 200 B.C. The word asparagus is derived from the Persian word “asparag”, which meant shoot. It loves sandy, well drained soils, which may explain its roots in Eurasia and seaside dunes along the Mediterranean Sea and the British Isles.

Fresh asparagus can be prepared in many ways (including being wrapped in bacon!) and contains glutathione, a potent antioxidant. It is well known for its detoxifying properties and is a good source of fiber, folate, iron and vitamins A, C, E and K.

Furthermore, it is a natural diuretic, which may be beneficial for individuals with high blood pressure and other heart-related conditions. Asparagus also contains inulin, a prebiotic which may support the beneficial bacteria in our gut.

Asparagus is always an interesting conversation piece. Yes, eating asparagus may make your urine smell funny. Our bodies convert asparagusic acid into sulfur-containing chemicals that stink — but some of us are spared from the pungent aroma (anywhere from 20% to 40% of the population can’t detect the smell, but it is there).

Yes, purple asparagus is an actual variety, but white asparagus is not a special variety. When the spears emerge from the ground, the sunlight turns the stalks green, and then six inches of dirt is piled on top of the plants so that the stalks can grow underground. When the tip breaks the soil surface, farmers probe under the ground with a special knife to cut the stalk, which is now all white.

This vegetable also loves sweet soil, so you may have to add some lime to raise the pH to at least 6.5. If you do not know the soil pH, take a sample and send it to the WVU Soil Lab.

Work lime deep into the soil so it can start to incorporate immediately. Research at Michigan State University shows that low pH in asparagus fields (below 6.5) are more conducive to the growth of the Fusarium fungi. Fusarium root rot is generally what eventually kills asparagus plants.

I receive a few calls every year about mowing asparagus ferns, so I will explain how this perennial vegetable grows. The plant is composed of ferns, crown and a root system. The ferns are not true leaves but are stems that will capture and transfer energy to the crown.

The crown is a collection of rhizomes (modified roots) and lateral roots that will initiate new ferns. Spears which are not harvested develop into a large fern which manufactures and stores energy in the crown.

Thus spears (what we harvest to eat) are actually immature ferns. Ferns should never be pruned or cut back. The asparagus fern is the “factory” that supplies energy to the crown and storage roots for next year’s crop.

Keep in mind asparagus is a perennial vegetable, so think long and hard about where you are going to plant. Asparagus beds may last 20 years, so site selection is crucial. Asparagus does not tolerate saturated soil conditions, so the site must have well-drained, loose, rich soil.

Asparagus is propagated with crowns, which are transplanted in a deep trench. Dig the trench 4-6 inches deep and use an inch of compost or apply good phosphate fertilizer before planting. Space the crowns 12-18 inches apart in the trench.

Keep rows about four feet apart so the ferns can close canopy and shade weeds during the summer. Cover the crowns with about 2 inches of soil, and as the ferns emerge and grow, gradually fill in the furrow through the summer.

I recommend ordering one year-old grown crowns from a reputable nursery. They are small enough that they don’t suffer so greatly from transplant shock. Two-year old crowns don’t do as well because they are so big that the transplant shock cancels out any benefit from the larger crown size.

Many home gardeners enjoy growing plants from seed. However, this is very difficult with asparagus. Researchers tried direct seeding many years ago without much success.

Let’s talk varieties. Asparagus is dioecious, which means there are separate male and female plants. I suggest planting the improved all-male varieties, which includes all the “Jersey” types developed by the Rutgers University Breeding program. These include Jersey Supreme, Jersey Knight or Jersey Giant.

Original plantings of asparagus in the United States are mostly one of the Washington varieties. This consists of Mary, Martha or Waltham Washington, which are unimproved heirloom varieties.

What hybrid means in the case of asparagus is that it is “all male.” In an heirloom bed, you will have an equal number of male and female plants. You will not be able to tell the difference until berries appear on the female plants. Female asparagus plants produce numerous bright, red, berry-like fruits with seeds that can become volunteer weeds in the garden or field.

Male asparagus plants (Jersey types) produce more spears relative to female plants. Male plants produce more spears than female plants because no energy is put into developing fruit and seed. The yield advantage for hybrids (Jersey types) is about 50% greater than heirlooms with male and female plants.

Delay harvesting spears until the third year of your planting. This will send all the plant’s energy into developing a strong root system. Harvest asparagus when it is about 5-8 inches tall, by snapping off spears.

The picking season lasts about six to eight weeks, harvesting every one to three days.

Snapping it off generally breaks the spear off above the woody, high-fiber section, eliminating the need to trim snapped asparagus. Field harvesting should cease when the majority of spears have a diameter the size of a pencil, called whips.

Most of the fiber in asparagus is in the skins, making the larger spears much more tender (opposite of what you think). Asparagus has a very short shelf life and should be immersed in cold water after harvest and immediately refrigerated to maintain quality.

Contact me at the Wood County WVU Extension Office 304-424-1960 or email me at jj.barrett@mail.wvu.edu with questions.

Good luck, and until next time, Happy Gardening!