If, like me, you’re a huge fan of growing your own food to cut down on grocery bills, you may consider this lovely perennial vegetable. In this article, I’ll show you how to grow asparagus in your own home garden. Use these tips to up your yield count and grow healthy plants that taste excellent.
This healthy green is easy to add to a wide range of home-cooked meals, and is easy for beginners to grow. Plus, just-picked, fresh asparagus tastes much better than store-bought.
Just remember that you must remain patient when it comes to growing this veg. Asparagus is a perennial, so when you grow it, expect it to be nearly invisible the first year, grow slowly the second year, and explode into a mass harvest the third year.
This is the “sleep, creep, leap” progression that’s common with pretty much all perennial vegetables.
When choosing an asparagus variety, it’s important to pay attention to the variety’s sex. Asparagus plants are monoecious, which means that each plant is either female or male. Some varieties come in all-male plants because they’re considered more productive and yield a larger harvest. Since they don’t produce seeds, the all-male varieties can focus on growing more shoots.
You might want to choose this kind of all-male variety if you want to grow a high yield. Twenty-five all-male plants are enough to feed a family of four, but you can double this amount of plants when you plant if you prefer a standard asparagus variety. Consider the following popular all-male varieties:
- Jersey Knight
- Jersey Giant
- Jersey Supreme
Other popular varieties include:
- Martha Washington
- Connovers Colossal
- Pacific Purple
- Purple Passion
Varieties may differ based on how tall or tick the spears grow, and the shape may also vary. Keep in mind that white asparagus is created by a different set of care and nutrition needs.
How to Plant Asparagus
Before planting your asparagus, find a location where it can live long-term. Most crops grow in the same area for over 20 years. Raised garden beds are perfect for your needs, and you can build your own simple DIY raised bed in no time. You can prepare a current bed by removing any weeds from the previous year and adding in plenty of compost to the soil.
Because asparagus is a warm-weather crop, you may also consider planting the crop in a greenhouse or cold frame. This could allow you to start the crop during February and maintain minimal transplanting to reduce the amount of shock the plants can suffer. Greenhouses are particularly useful in colder regions as well.
You can grow asparagus one of two ways: planting from spear or seed.
Growing from Spear
If you start growing asparagus from a spear or a year-old crown, you can save a years’ worth of grow time over growing the plants from seed. Not only can you harvest the crop sooner, but you can also buy crowns from your local nursery to plant immediately. Two-year-old crowns, however, don’t work as well. They commonly suffer from transplant shock, which makes them take just as long as growing from seed.
When growing asparagus from a crown, soak them in a compost tea for about 20 minutes prior to planting. Dig a trench that’s around 6 inches deep and 12-inches wide in your prepared raised garden bed and place the crowns about two feet apart.
Then cover them with at least two inches of soil. Add a couple more inches of soil in another two weeks, and so on until the soil is mounded a bit above surface level.
Growing from Seed
Growing asparagus from seed takes more patience, but it’s well worth the wait. In fact, seed-grown asparagus are less likely to suffer transplant trauma, more affordable than buying crowns, and produce a larger yield on average.
If you grow from seed, you can also select only the male plants to a larger yield no matter what variety you select. Simply discard the female plants that grow in by looking at the tiny flowers with a magnifying glass. If you see 3-lobed pistils, they’re female. Males display larger and longer blossoms than female flowers.
When to Plant
A colder, northern area requires you to start the seedlings indoors. You can start sowing the seeds in a newspaper pot as early as February. Place them in a sunny window and keep the temperature above 77 degrees F until the seeds sprout, then lower the temperature to between 60 and 70 degrees.
After the final frost of the season, you can plant the foot-tall seedlings. Weed out the female plants, and the following spring, you can transplant the male plants to a permanent place in your raised garden bed.
If you live in a warm area, you’re still better off starting the plants around 12-14 weeks before setting the seedling outside. If you’re not worried about frost, plant asparagus directly in early spring as soon as the soil is ready to be worked.
You can also plant asparagus in the fall to grow over the winter if you have a greenhouse.
Asparagus thrives in most areas. It survives winter freezes and dry periods but doesn’t so as well in mild, wet areas like Florida or the Gulf Coast.
Although the plant can tolerate partial shade, it thrives in full sun. With more sunlight, the plants grow more vigorously and are less likely to fall to disease.
Light, well-draining soil is best, as they’re more likely to warm up quickly during the spring.
Seeds take around 3 weeks to germinate, which is why many people prefer to start the seeds indoors or in a greenhouse around mid-February.
Space Between Seedlings
When planting asparagus from seedlings, place the transplants at least 8 to 10 inches apart.
How to Care for Asparagus
With adequate care, your asparagus crop will be one of your first spring harvests.
Water the plants regularly for the first two years and reduce after the plants are mature. Avoid overwatering or the roots will rot.
Asparagus plants must remain between 75-85 degrees during the day and no lower than 50-60 degrees at night. Because the plants only grow new shoots with soil temperatures over 50 degrees, you must maintain warmth.
Weeding and Mulching
Mulching asparagus is highly beneficial for a few reasons. First and foremost, it protects from plants from weeds and frost.
Straw is the perfect mulch for asparagus. Remove any weeds you see immediately, as they’ll compete with asparagus spears and reduce your crop numbers. You’ll also want to weed out all the female plants before winter to encourage the male crop to produce.
The mulch will also protect the plants from the cold during winter. If you notice any young spears turning brown, appearing withered, or feeling soft to the touch, you may have frost damage. Cover the young spears with mulch or newspaper over freezing nights or invest in row covers if you live in a colder region with harsh winters.
Fertilize asparagus crops in the spring and fall with a top-dressing liquid fertilizer or compost tea.
Pruning and Wintering
You don’t have to prune back the plants before wintertime. Simply leave any foliage the cold kills off with the mulch along the bed for added protection against the frost. When the weather begins to warm up, you’ll want to remove the fern-like foliage on the plants. Do this before new growth starts up in spring to protect them from disease and pests.
If you’re growing white asparagus, which is milder in flavor and cultivated differently than green asparagus, try heaping either soil or mulch over the raised bed in the spring before new spears pop up.
Common Problems to Growing Asparagus
Keeping foliage healthy is required when learning how to grow asparagus. Unfortunately, the tasty leaves attract a few pests that you’ll need to deter.
Asparagus beetles are the main culprit. They chew on the spears during the spring and attack the foliage in summer months. The pests grow to around 1/4-inch and appear with metallic blue-black bugs with 3 either yellow or white spots on the back. These beetles lay dark-colored eggs on the leaves that are difficult to spot, and they hatch into gray or brown larvae.
You can spray your plants with insecticidal soap or pick them off by hand. You can also use these care methods to control infestations from the 12-spotted asparagus beetles—another main pest. They’re red-brown in color with 6 black spots on each wing cover.
Asparagus miners are other common pests that feed on the foliage. You’ll notice their presence when your stalks display a zig-zag pattern of tunnels. Any infested ferns must be destroyed immediately.
Many diseases may also cause you to start a new bed away from infested crops. Asparagus rust is one such common disease, which shows up in red-brown spots on the leaves and stems. You can plant resistant cultivars to counteract the rust.
Fusarium wilt is another disease to avoid by making sure you only buy crowns from a reputable garden nursery. It causes the spears, stems, and leaves to appear like they have lesions around or just below the soil line. Crown rot, another common transplanting issue, is easy to prevent by planting in a raised bed and maintaining soil drainage. Otherwise, the spears may turn brown near the soil.
How to Harvest and Store Asparagus
As mentioned, you can’t harvest the asparagus growing in your raised garden beds for at least the first two years. During this time, the plants work on establishing deep and prosperous roots. The third year, you can begin to pick the spears for the first time.
Start slowly by harvesting the plants in the early spring only over a four-week period of time. The following year extends this harvest period to 8 weeks. Harvest asparagus spears around every 3 days during early spring and increase the frequency to twice per day during summer to keep up with production. Cut the spears from the plant using a sharp knife, or simply snap the spears off at ground level using your hands.
To store asparagus, clean the crops and use the refrigerator. Place asparagus in a glass with an inch of water, with all the ends in the water. Cover with a plastic bag and place the glass directly in the fridge. You can store it this way for a week or so.
A Final Tip
Now that you know how to grow asparagus, consider some ways you can grow a better crop. If you live in a colder area, for example, or notice your plants suffer from the cold, try growing asparagus all year long in a greenhouse. Additionally, try planting the asparagus seedlings near your tomato crop, where the plants can benefit from each other. You can try a simple raised garden bed to reduce standing water, or select an -all-male variety to help you grow more.