However, the asparagus plant is worth the wait. The fact that it’s a perennial means that after the heavy labour, your asparagus will crop up year after year. Winter is the season to plant asparagus crowns, which are the roots and rhizomes of a year-old plant.
If you want to learn how to cultivate asparagus, here’s everything you must know regarding the plant. This thorough asparagus guide will lay out every step, from planting to harvest.
About Asparagus
Asparagus spears, cut when 15-18 cm high, are enjoyed as cooked or raw food. They are flavourful, crisp, and tender. Spears are the succulent young shoots of the plant with scale-like ends. They spring from underground buds called “crowns.” If left to grow, they produce leaves and are called “ferns.”
Green asparagus is the most favoured and the most readily available. White asparagus is the green variety grown without light and doesn’t produce chlorophyll. This is done by piling a soil mound over the emerging spears or covering it with black plastic. The final product is a smooth, thicker, and tender crop than green asparagus.
Purple asparagus produces thicker spears that contain antioxidants, with a peak season from spring through early summer. It is naturally less fibrous and thus more tender than other asparagus types. However, it reverts to green when cooked.
Types of Asparagus
- Purple Passion – Great for freezing and have a distinctly nutty taste
- Mary Washington – The most popular variety, along with Martha Washington, because of high tolerance for different growing conditions
- Jersey Giant – Has a thick stalk that gives it a very meaty and more intense taste
- Apollo – Produces medium to large diameter spears with slightly tapering spears and tight tips
- Precoce D’Argenteuil – Has a very sweet taste, with a whitish-green spear and rosy pink tip
When To Plant Asparagus?
Some varieties can be planted during early fall while the soil is still warm from the heat of summer. This plant is the earliest vegetable for most gardeners. Enjoy the plant even while or before you’re planting most other crops.
Asparagus beds can be productive for 15 to 20 years, and well-maintained beds are known to produce for 30 years. And because asparagus remains fruitful for ages, it’s essential to plant the best variety for your area.
Should You Grow From Crowns Or Seed?
How To Grow Asparagus From Seed
It needs the patience to grow your asparagus patch from seed. Still, there are benefits from the additional wait. You should plant asparagus seeds indoors or in a greenhouse from mid-February to May or 10 to 12 weeks before your area’s last frost date.
Begin by sowing single seeds in seed trays or small posts. Pre-soaking the seeds in lukewarm water for a few hours before planting can expedite germination. Sow asparagus seeds about 1/2 an inch deep in fertile potting soil. Then, place the pots/trays in full sunlight as the seeds require soil temperatures between 70 and 85°F to encourage growth. Dampen the soil every day with a water spray bottle. This step must be fulfilled at the start of spring.
If successful, you should see indications of germination within 2 to 8 weeks.
Transplant plants to the permanent bed when seedlings are 3 inches tall. Plant each seedling about 4 inches deep, with spacings of 12 – 18 inches apart. Cover with a layer of soil and water well.
These perennial plants are either male or female. Male plants usually produce larger and more spears because they don’t need to spend energy on seed production, while female flowers have well-developed, three-lobed pistils. When tiny flowers appear, weed out all female plants.
Let the male plants get some exposure to cold temperatures to become dormant and return stronger the next spring. You can then start regularly harvesting the spears in the third year. Meanwhile, control weeds and insect pests and water the asparagus spears as necessary.
How To Grow Asparagus From Crowns
Asparagus crowns are the roots of 1 to 2-year-old asparagus plants. They produce edible veggies much faster than seeds due to their advanced growth stage.
So, if you are going with crowns, make sure they are hard and fresh with a faint smell of asparagus. Any wilted and soft crowns with a foul scent are not advisable.
How To Grow Asparagus Plants?
Preparing Your Asparagus Beds
Prepare the bed as early as possible. Remove weeds and grasses when preparing the asparagus bed, and continue weeding while the asparagus plants are still young. Asparagus roots create a firmly twisted mat, making removing weeds demanding.
Dig a trench 12 to 18 inches wide and 6 inches deep (8 inches in sandy soil) down the center of the prepared bed. Since asparagus must be planted six to 12 inches below the surface, a shallow asparagus bed will only create problems.
Build mounds down the centre of the trench to bury the crowns. A nice approach is to utilize compost for the mounds, though the garden soil will also suffice. Separate each mound about a 3-inches apart, and it’ll thrive into a lovely thick patch.
Because asparagus live for years on end, amend their field with an abundance of nutrients from the very beginning. Apply 0-20-0 fertilizer (the numbers denote the ratio of nitrogen N, phosphorus P, and potassium K, respectively) at the bottom of the trench and blend it with the topsoil that has been removed. You may also spread organic fertilizer – a layer of bone meal and rock phosphate, a natural mineral powder that stimulates root growth.
Compost is a real champion in helping enhance soil’s fertility and structure. When you incorporate compost and organic matter, allow the soil to sit for a few months to enable the nutrients to penetrate. Till the soil deeply several times before planting so that it will be in fine tilth at the time of planting.
Planting The Asparagus
Once you finish preparing the trenches and placing the crowns, top-dress them firmly with compost to submerge each crown about 2 inches deep. And then water them.
Adding a light compost or mulch of dried grass clippings will aid in maintaining moisture in the soil, controlling weeds, and even providing some protection against any unforeseen late frosts.
Over time, you will see asparagus shoots appearing. This is when you are needed to add two more inches of topsoil to the trench, leaving a few inches of the shoots exposed above the surface. As the plants grow, add more soil around them gradually until it’s level with the asparagus bed. After filling the trench, the soil should be mounted delicately to prevent standing water around the spears.
Note: Don’t interplant other vegetables in the same bed. Asparagus can’t stand being with other plants.
Caring For Asparagus
Mulching & Watering
After clearing any obvious weeds, spread mulch to cover any left weeds. You can mulch with compost, leaves, grass clippings, or straw.
Water often during the first two years after planting. If you live in a dry region, you may want to install drip irrigation or a soaker hose. As asparagus grows, it takes over most weeds and leads long, soft roots deep into the ground, so watering is less necessary. You can decrease the frequency to every two weeks.
Fertilizing
Cover the soil yearly with compost to keep the soil rich and help nourish the asparagus plants. Resolve this in early spring before the shoots emerge or during fall after the spears have died back and been clipped to the ground. Asparagus is a heavy feeder, so give plants blood and bone fertilizer in spring and spread composted manure in winter.
Temperature
Pests & Diseases
Asparagus rust, fusarium crown, and root rot can all be problems. Apply seeds in sterile soil rather than buying plants, and avoid planting new asparagus near the infected site. Rust needs moisture to spread; hence, avoid giving excess water on spears or ferns.
Cultivating ladybugs, hummingbirds, and green lacewings relieve aphids. To spot aphid damage, look for Asparagus growing deformed and misshaped, curled, or yellow leaves. Removing dead ferns can also lessen damage from aphids and diseases. Reap all the spears, so they don’t spread diseases, and observe throughout the off-season for pests or infections.
How To Harvest Asparagus
In the second year, clear away any symptoms of dead ferns. Besides, the crop will need frequent mulching as it will engage in a maturing stage. Some home gardeners usually harvest a handful of spears in the first year; however, it damages the rootings.
The following season you can start harvesting your asparagus for two weeks.
Examine your plant on alternate days for harvest-ready spears. Spears proliferate and may get too woody in a blink of an eye! As soon as an asparagus spear begins to sprout and have leaves, it’s too fibrous for chewing. Harvest spears when the stems are 8 to 10 inches long and between 1/2 and 3/4 inches thick. (Note that thinner spears will be tougher to chew, and thicker spears will have a better texture.)
In early spring, harvest spears every third day; because the weather warms, you might need to reap your crop a couple of times daily. The right time to reap is in the morning when temperatures are still cooler and before they have bathed in the heat and stress of the sun.
Bend the spear sharply and snap it using your thumb and forefinger. You can also wield a sharp knife or scissors, clipping at ground level. While some gardeners like to cut beneath the soil line, be mindful that this could cause unintentional cutting of surfacing shoots nearby if you’re being careless.
Cease harvesting spears if you witness reduced production in your asparagus plants, and the spear’s width is less than pencil size. Allow the remaining stalks to grow to strengthen roots, replenish nutrients, and store energy for next year’s spear production.
How To Store Asparagus
Soak freshly cut spears in cold water instantly to preserve their sugar content.
To store, wrap the asparagus in wet paper towels and place them in a plastic bag in the crisper drawer. Don’t overcrowd the bags. You can also store asparagus by putting the spears upright in a jar with an inch of water. Cover with a clean plastic bag, securing with a rubber band – allow enough room for air circulation.
Store at about 36°F (2°C) for up to 10 days.
Here is to planting your delectable crop of asparagus in your garden. Just follow the guidelines, and you can enjoy your own veggies in the coming years!
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