Asparagus, or garden asparagus, scientific name Asparagus officinalis, is a perennial flowering plant species in the genus Asparagus. Its young shoots are used as a spring vegetable. It was once classified in the lily family, like the related Allium species, onions and garlic. It originated in Europe, North Africa, and West Asia and has been consumed for more than 2,000 years. It is widely cultivated as a vegetable crop.
Asparagus spears are the straight young shoots of the plant, with scale-like tips. Later in the season, the foliage matures into an airy, light-green, fern which changes to a golden color in the fall. This perennial is typically planted from roots, or crowns, in early spring. Sometimes referred to as “sparrow grass,” asparagus grows naturally in sandy soils and temperate, Mediterranean climates.
Table of Contents
0.5 - 8 feet
1 - 3 feet
6.5 - 7.0
Types of Asparagus
Asparagus plants are either male or female. Female plants produce berries; males plants do not expend energy on berries so they can be up to three times more productive than female plants. For this reason, growing male asparagus plants is often preferred.
At first glance, all asparagus types look almost identical. Apart from different colors, they all have the same slender shape and length. But a closer look tells you that there’s a reason one type is different from another. Also, not all types are easy to grow in your garden. While you can grow the green or purple asparagus with 6 to 8 hours of sunlight, the white type requires total darkness to grow. Here are the main types of asparagus.
Green Asparagus: The most common type of asparagus and the one you’ll most likely find in your local supermarket. It has low fiber content, a smooth texture, and good flavors. Moreover, when you cook it, the asparagus will maintain those flavors. A healthy food choice, green asparagus is rich in antioxidants especially anthocyanin. Its sweet taste is due to the higher concentrations of sugar in the young spears.
White Asparagus: You can think of white asparagus as the bleached version of green asparagus. Both types have the same size, shape, taste, and nutritional values. The only difference is one of them is white and the other is green. And the only reason you’d want to mix the different types in your garden or in your dish is to create a more appealing visual effect. However, white asparagus doesn’t like bright light and prefers to grow in dim to totally dark conditions.
Purple Asparagus: The reason this type has a deep purple color is because of the high content of anthocyanin. So it’s by far the healthiest asparagus type you can consume for your cardiovascular system. In terms of texture, the spears of this type remain succulent and tender even when they grow long and thick. So if you’re looking for a sweet, tender, and healthy asparagus, grow the purple type.
Wild Asparagus: This type of asparagus grows in the wild and tends to be thinner and less productive than the other three. It has a more natural taste as it lacks both the high sugar content and antioxidants that you find in the cultivated types.
Apollo asparagus has a dark green color with purple tips. It has medium or large stalks that are very smooth and uniform. This asparagus can be grown in both cool and warm weather. It takes less time to mature than other varieties.
Given the outstanding features of Apollo asparagus, you can use it in a lot of ways. It is best to enjoy it fresh. You can also freeze it to use it up later. People also roast it and serve it as a side dish for fish.
Mary Washington Asparagus
Mary Washington is a medium-sized variety with a length of 8 inches. It is very popular in America. The stalks have a deep green color, and the tips are light purple. The shoots are long, tapered, thick and bred for rust-resistance.
Notably, this type of asparagus is very uniform, which looks amazingly appealing. Its taste is also very delicate.
Atlas asparagus has a rich and nutty taste. The stalks are about 8 inches long and have a dark green color. It also has some purple shades on the bud scales. Its spears are larger than other types of asparagus.
The best place to grow Atlas asparagus is where the temperature is between 45 and 84 degrees Fahrenheit. So it can be planted in both cool and hot weather. It should be placed under the sunlight for at least 6 hours a day.
You should collect it before it is longer than 8 inches so that its flavor and texture can retain after cooking. The Atlas asparagus plant is very sturdy. It can withstand frost, fusarium, and diseases.
Precoce D’Argenteuil Asparagus
This green asparagus has a delicious sweet taste. It will become tender after cooking. It is very popular in European countries, especially France. It is used to make salads. People also roast and saute it and serve it in gourmet restaurants.
In terms of appearance, it can be up to 3 feet long. It is mainly pale green, yet the tips have a gorgeous rosy pink hue.
Viking KB3 Asparagus
Viking KB3 is a variety of Mary Washington asparagus. It is a productive, sturdy, and easy-to-grow type of asparagus. It lives well in every weather condition. It also takes a short time to mature. When mature, it is about 10 inches long, and the stalks are as thin as pencils. The shoots are succulent. If you harvest it later than that, the shoots will get chewy.
It is best to make salads with this variety. You can also roast it with garlic and olive oil to make delicious vegetable dishes to accompany heavy main dishes.
Jersey Giant Asparagus
With an incredibly sweet, meaty taste and tender texture, Jersey Giant asparagus is a super versatile variety. You can eat it raw or add it to salads and other savory recipes. It is a large variety with a maximum length of 7-9 inches.
You should note that if you let it stay on the ground after it reaches the maximum length, it will get sinewy and is not delicious anymore. This variety is the growers’ favorite because it can be grown in most weather conditions. In addition, it can fight against diseases and fungi, especially fusarium.
Jersey Knight Asparagus
Jersey Knight asparagus may be the most delicious type of Jersey asparagus. It is also highly productive. It can produce almost 4 times more crops than other types.
This variety is heat-tolerant and disease-resistant. The spears are green while the bracts are purple.
Jersey Supreme Asparagus
Jersey Supreme is a hybrid variety that is normally harvested earlier than other varieties. It is very productive, disease-resistant, and cold-hardy. Its spears are incredibly tasty. It is best to grow it in sandy soil and in growing zones 3-8. The stalks come out uniform and delicious.
Amazingly, this type of asparagus can withstand fusarium wilt and rust. The longer you leave it on the ground, the more stalks it produces.
This variety tastes a little bit bitter when uncooked. But after cooking, its amazingly delicious taste will stun you. What is special about Millenium asparagus is that it is very productive, cold-hardy, and adapted to most soil types.
Grande Hybrid Asparagus
Grande Hybrid asparagus has large spears. The spears are dark green in color, and the bud scales have a purple hue. They are smooth and cylindrical in shape. As the name says, it is a hybrid variety and is very productive.
UC 157 Asparagus
This hybrid type of asparagus was developed in 1978 with both male and female plants. It produces an exceptionally high yield, making it one of America’s most viable and popular varieties. This variety does best in warmer climates but grows well in all growing zones. It is very resistant to most diseases to affect asparagus. It is pale green in color and produces uniform stalks.
Purple Passion Asparagus
This variety is purple when raw. A sweet purple variety. However, when cooked, it turns light green. Yet the spears are still purple. You can spot out Purple Passion asparagus by looking at its bracts. They look like leaves.
Purple Passion asparagus has a distinctive nutty and tender taste that is perfect for making salads and roasted dishes. You should note that after you cook it, its purple color will turn white. It is one the most tender and delicious types of asparagus. You can also keep it fresh for a long time by freezing it.
Stewarts Purple Asparagus
Stewarts Purple asparagus has a stunning color. Yet when cooked, the lovely purple hue will fade away. This variety is a great choice if you love sweet asparagus since it is much sweeter than green asparagus.
You can add fresh Stewarts Purple asparagus to salads, steam it, or enjoy it with dressing. Its color will stay if you steam it.
Pacific Purple Asparagus
This New Zealand variety is fascinatingly sweet and tender even when it is cooked. People love to serve it raw with dipping sauce or steam it because its purple color will fade away if other cooking methods are used.
It produces more crops than Purple Passion and green asparagus. The leaves of Pacific Purple asparagus are very beautiful. It will make your house look more refreshing during summer.
Given that asparagus is a perennial plant that comes back year after year in the same spot, it’s important to select a proper planting site where it will thrive.
Choose a site that gets full sun (6-8 hours of direct sunlight).
Place the asparagus bed toward the edge of your garden, where it will not be disturbed by the activity of planting and re-planting other areas.
Ensure the bed will drain well and not pool with water. Asparagus does not like to have its roots get too wet. If you do not have a site with good drainage available, consider growing asparagus in raised beds instead. Learn how to make a raised garden bed here.
Asparagus thrives in neutral to slightly acidic soil (pH of about 6.5).
Eliminate all weeds from the planting site, digging it over and working in a 2- to 4-inch layer of compost, aged manure, or soil mix. (Learn more about soil amendments and preparing soil for planting.)
The soil should be loosened to 12 to 15 inches in depth to allow the asparagus crowns to root properly and not be disrupted by rocks or other obstacles.
When to Plant Asparagus
Plant asparagus crowns in the early spring, as soon as the soil can be worked. Many gardeners plant at about the same time as potatoes go in the ground.
Asparagus is usually grown from 1-year-old plants called “crowns,” but it can also be grown from seed. Starting with asparagus crowns, however, eliminates the year of tedious weeding that comes with starting from seed, and will speed up production overall.
A few varieties, such as open-pollinated ‘Purple Passion’ and hybrid ‘Sweet Purple’, can be grown from seed. Start seeds indoors in spring and set out the seedlings when they are 12 to 14 weeks old, just after your last spring frost.
Soak seeds in water for up to 24 hours before sowing.
Sow seeds in moistened peat or seed-starting soil in flats or peat cups.
Once plants reach 12 inches in height, harden them off outdoors for a week.
After the last spring frost, transplant the young plants to a temporary garden bed. Once they mature in the fall, identify the berry-less male asparagus plants and transplant them to your permanent planting site, removing the less-productive female plants.
How to Plant Asparagus
Plant crowns deeply to protect them from the cultivation needed for annual weed control.
Dig a trench of about 12 to 18 inches wide and 6 to 8 inches deep. If digging more than one trench, space the trenches at least 3 feet apart.
Soak the crowns briefly in lukewarm water before planting.
Make a 2-inch-high ridge of soil along the center of the trench and place the asparagus crowns on top of the mound, spreading their roots out evenly.
Within the trench, space asparagus crowns 12 to 18 inches apart (measured from root tip to root tip).
Once you get to this point, you can follow one of two planting methods: the traditional “little-by-little” method or the easier “all-at-once” method.
Once the trenches are dug and the crowns are set out:
Cover the crowns with compost and topsoil, burying the crowns 2 inches deep. Water in.
As the season progresses and spears grow to be 2 to 3 inches tall, add 2 more inches of soil to the trench, being careful not to bury the spears completely.
Once the spears again grow through the layer of soil, add an additional 2-inch layer of soil. Repeat this process until the trench has been filled to ground level. Depending on how deep you dug your trench, you may need to add soil 1 to 2 more times throughout the season.
After you’ve filled the trench completely, mound the soil slightly to prevent water from pooling around the emerging spears.
Some gardeners simply fill in the trench with soil and compost all at once. While it’s thought that the traditional method results in stronger plants overall, gardeners don’t typically have any issues result from the “all-at-once” method, either. As long as the soil is fairly loose, the spears won’t have a problem pushing through to the surface.
Asparagus plants grow best in full sun. Without enough daily sunlight, you will wind up with thin spears and weak plants that are prone to problems.
For a long-lived perennial like asparagus, it pays to take the time to improve your soil. Work in plenty of organic matter and make sure the soil pH is in the neutral 6.5 to 7.0 range. Also get rid of any weeds and large stones in the area. The soil must drain well so the plants are never sitting in water.
Asparagus needs regular watering, especially while young; give it 1 to 2 inches of water per week during its first two growing seasons; give older plants about 1 inch per week. Give them a good start when you first plant them and you'll have fewer problems in future years. Consider adding drip irrigation or a soaker hose to the asparagus bed.
Temperature and Humidity
During the growing season, asparagus prefers a temperature of 70 to 85 degrees Fahrenheit during the day and 60 to 70 degrees at night. In the spring, it will begin to grow shoots when the soil temperature reaches 50 degrees. Any frost after the shoots start growing will cause discoloration. You may see slow growth with temperatures above 85 or below 55 degrees.
When preparing your asparagus bed, add compost and an all-purpose organic fertilizer to the trench, as well as rock phosphate, a natural mineral powder that promotes root growth. These nutrients will help your asparagus develop a good, strong root system. To keep the soil rich and help feed the asparagus plants, top dress the soil annually with compost. You can do this in early spring before the shoots appear, or in the fall after the fronds have died back and been cut to the ground. Asparagus is a heavy feeder, and you should also give it a dose of fertilizer in mid-spring when it is actively growing.
Skip the harvest in the first year and the second year, if possible. Ideally, wait three growing seasons before harvesting in order to allow the crowns to become fully established.
If you have young plants, the season may last 2 to 3 weeks. However, established plants produce longer—up to 8 weeks.
Check your plant every other day for harvest-ready spears. Spears grow quickly and may become too woody before you know it! Once an asparagus spear starts to open and have foliage, it’s too tough for eating.
Harvest spears when they reach 8 to 10 inches in height and between 1/2 and 3/4 inch thick. (Bear in mind that younger, thinner spears will be more tender, so harvest according to your own taste.)
To harvest asparagus, simply cut the spears with a sharp knife or scissors at ground level.
Stop harvesting spears when the diameter of the spears decreases to the size of a pencil.
After harvest, fertilize your asparagus in early summer. You can top-dress with a balanced organic fertilizer, or scatter another inch of rich, weed-free compost over the decomposing mulch.
Do NOT cut down the remaining ferns in summer or you will ruin your asparagus bed. Allow the ferns to grow and mature; this replenishes the nutrients for next year’s spear production. Always leave at least two or three spears on the plant through the growing season.
Only cut back asparagus ferns AFTER the foliage has died back and turned brown or yellow. This is usually in early winter after several hard freezes. Cut the ferns back to the ground.
Fertilize the bed with a 1-inch layer of rich, weed-free compost or manure topped with 3 inches of straw, rotted sawdust or another weed-free mulch. Clean spears will push up through the mulch in spring.
How to Store Asparagus
Plunge just-cut spears into cold water immediately to preserve their sugar content.
Asparagus does not keep for very long after it’s picked, so be sure to eat it within two or three days from harvest.
To store, bundle the spears together, wrap the stem ends of the spears in a moist paper towel, and place the bundle in a plastic bag. Store in the crisper drawer of your refrigerator.
If you have enough space in your fridge, you can also store asparagus by placing the spears in a cup of water. Keep about an inch of clean water in the cup.
Asparagus plants need to be cut to the ground each year before the new growth starts. The timing is up to you. You can remove the stalks in the fall or winter after the leaves have turned yellow and died back naturally. The advantage of early removal is that it prevents pests, such as asparagus beetles, from overwintering in the stalks. Leaving the stalks standing through the winter, on the other hand, has the advantage that the plant debris can hold snow, which protects the asparagus crowns in freezing temperatures. In any event, the dead stalks must be removed in the spring before the new growth starts.
Pests & Plant Diseases
Asparagus does not have too many problems in the garden. Fusarium wilt can be a problem with older varieties, but you can avoid it by planting resistant hybrid varieties. The biggest pest is the asparagus beetle. Keep watch for them as the spears emerge in spring. They're most active in the afternoon. Hand pick the beetles and drop them in a bucket of soapy water when there are only a few. Otherwise, diluted Neem oil should keep them under control.
Benefits of Asparagus
Supports in Digestion: Asparagus contains significant amounts of inulin, a unique type of carbohydrate called “prebiotic”, that help to promote the growth of healthy bacteria like Lactobacilli and Bifidobacteria. The fiber content in asparagus is also beneficial to the digestive tract.
Good for your Heart: The nutrient content in asparagus play an important role in keeping the heart healthy. Asparagus is rich in complex B-vitamin and fiber that can help lower the risk of heart diseases, high blood pressure and stroke.
Fights Cancer: The antioxidant and anti-inflammatory compounds present in asparagus can alter metabolic activity in the body’s cell and ultimately help prevent them from becoming cancerous. A research found that the combination of amino acid with folate and vitamin B6 in asparagus has been shown to have cancer-fighting properties.
Prevents Diabetes: A number of studies have found that eating asparagus may help to control type 2 diabetes. It is useful for improving insulin secretion, and therefore helps to lower the risk from type 2 diabetes.
Rich in Antioxidants and Anti - Inflammatory Properties: Asparagus contain high amount of antioxidants that can help remove toxins from the body. It also helps slow the aging process and keeps your skin looking young and healthy. The anti-inflammatory properties in asparagus such Vitamin C, Vitamin E and beta-carotene are very powerful and aid in reducing the risk of heart problems and type 2 diabetes.
Great source of Folic Acid: Asparagus is a rich source of folate or folic acid, which helps to prevent nervous system defects in babies.
The root and seeds are used to make medicine.
Its young shoots are used as a spring vegetable.
Asparagus can increase urine production and is also a good source of dietary fiber, folic acid, vitamin C, vitamin E, vitamin B6, and several minerals.