Asparagus Gardening

Asparagus Gardening, Asparagus officinalis, is a perennial vegetable crop that’s among the first ones to come to harvest with the onset of spring. It’s a flowering plant species belonging to the family Asparagaceae. It’s cultivated as a vegetable in most temperate and subtropical climates of the world for the succulent stalks that appear in spring. Asparagus is typically served cooked in stir fries, vegetable side dishes, soups, stews and salads. Besides being a good source of dietary fibers, asparagus is also rich in Vitamin B6, magnesium, calcium and zinc. It’s typically planted in early spring from roots or crowns and takes about 2 to 3 years to establish and start producing a decent harvest. However, once established, an asparagus crop can be productive for over 20 years!

Types & Varieties of Asparagus

Different Asparagus varieties exist, with distinct differences in colors, appearance and quality of spears. Asparagus plants can be either male or female. The newer cultivars are bred to be all male since the plants consume all their energies into the development of the plant instead of seed production, giving you larger and more abundant spears.

Common varieties of Asparagus:

Mary Washington – The most common asparagus variety is an heirloom and is a favorite among gardeners for the long green spears with purple tips that it produces. It’s rust-resistant and is ready for light cuttings in 2 years.

Jersey Giant – It is an all-male early yielding variety that’s bred for rust and fusarium wilt resistance and is cold hardy so it will perform exceptionally well in northern climates.   

Purple Passion – As the name implies, this variety produces purple spears, but the color fades with cooking. The attractive spears are sweet in flavor ready for harvest around April to May each year.

Apollo – this is a hardy asparagus that grows well in both cold and warm climates. It’s very disease resistant and yields a large crop with medium to large dark green sized stalks with a hint of purple on the tips.

Depending on how often you consume the vegetable, plant a garden with around 5 to 20 asparagus plants for every person. Since individual plants are spaced 3 feet apart, this makes about 12 to 60 feet of row for each family member.

Temperature and Timing for growing Asparagus

Asparagus are perennial vegetables that prefer a temperature between 70 to 85°F at daytime and the nighttime temperature should be between 60 to 70°F. Asparagus crowns are usually planted in spring as soon as the soil can be worked. Each year, young, tender shoots will appear in spring as soon as the soil temperature stays above 50°F in spring.

Sun Exposure and Soil Requirements

Asparagus plants grow best in full sun to develop healthy, thick spears. Without adequate sunlight, you’ll find thin, weak spears and the plants are more prone to diseases. Choose a well-drained garden bed for your garden and amend the soil with plenty of organic matter and remove weeds and stones from the area to prepare the land for a perennial vegetable that will stay in place and provide you with succulent spears for years to come.

How to Plant Asparagus

Asparagus can be grown from 1-year old crowns or seeds. Most gardeners prefer growing crowns since it gives a jump-start on the crop, eliminating some of the wait time before you can start harvesting the spears.

When growing from seeds, seeds are started indoors in early spring. Plant the seeds in a good seed starting mix filled in peat cups. Seedlings are transplanted outdoors once they are at least 12 weeks old and the last spring frost has passed.

By the fall, the plants will mature and you’ll be able to tell apart the berry-less male plants from the female ones. You can remove the female plants since they are less productive and allow more space for male ones to grow.

To plant crowns in the garden, prepare the soil to a depth of at least 12 inches, removing any hard stones or weeds that you find along the way. Amend the soil with 2 to 4 inches of compost and other organic matter.

Dig 12 inches wide and 6 inches deep trenches into the ground, spaced 3 inches apart from each other. Next, create a 2-inch tall ridge of soil along the center of the trench and place the crown over the mounds, spacing them 12 to 18 inches apart. Add about 2 inches of soil to the trench to cover 2 inches of the crown from the bottom. As the crowns grow taller, add more soil to the trench, 2 inches at a time until it reaches ground level.

Once the trench is filled with soil, add mulch to prevent weeds from taking over. During the first two years of growth, offer the crop 1 to 2 inches of water each week. Since asparagus is a heavy feeder, it will also need regular nourishment to keep up production. When asparagus gardening, top dress annually with compost before shoots start appearing in spring and fertilize with an organic fertilizer around mid spring when the growth is at its maximum.

Harvest

Generally, you should wait until the third year to start harvesting the spears.

• During the third year, only harvest a few spears for two weeks at the most and let the remaining spears develop undisturbed.
• During the fourth year, you can harvest spears that reach 5 to 7 inches in height by cutting them with a knife just above the soil level. You can harvest for up to three weeks.
• During the fifth year, the harvest time can extend up to six weeks.
• Following the fifth year, you can continue harvesting the spears all through the spring, as they appear from the soil.

Storing

Asparagus spears don’t do well in storage and are best consumed fresh, within two to three days from harvest. Wash the spears with cold water and dry them before storing. Bundle the stems, wrapping them lightly with a paper towel and store them in a plastic bag before refrigerating.

Pests and Diseases

Pests

• Asparagus beetles are a common problem with this vegetable. The insects cause spears to turn brown, ultimately defoliating the crop and diminishing harvest. Remove the beetles by hand or hose them with a strong spray of water.
• Cutworms attack the stems of young shoots, cutting them just above the soil level. Keeping the area weed-free and removing plant debris can prevent these from finding your crop. Remove them by hand as you find them.

Diseases

• Asparagus Rust is a fungal disease that shows up as pale green spots on newly emerged shoots. By summer, they turn into reddish brown lesions and then black by fall. Severe infection can cause defoliation. Choosing resistant varieties, ensuring air circulation and preventing excessive moisture in the soil can help prevent the infection.

Follow the guide above and you’ll have fresh, crunchy spears to harvest in just a couple of years – homegrown asparagus are worth the wait!