Asparagus is known for its delicate flavor and crisp texture and is classed as a nutritious vegetable that can be an excellent addition to any garden.
Growing asparagus is not only a rewarding experience but also an easy task for any gardener, regardless of their experience level.
You can break down the asparagus growth stages into seven transformations.
The first stage is germination, followed by emerging shoots and crown formation. After the shoots have emerged and the crowns are formed, foliage development and flowering occur. After that, the asparagus will produce berries before entering its final dormancy stage.
This article provides a comprehensive guide on successfully growing asparagus in your backyard, starting with selecting the suitable variety to harvest and storing the crop.
Whether you are a seasoned gardener or just starting out, you will find the information valuable and informative.
Asparagus Growth Cycle Overview
Asparagus is a slow-growing plant that can take a few years to reach maturity. After planting, it usually takes 2-3 years for the plants to produce an entire crop.
In the first years, asparagus plants establish and grow a root system to support the production of shoots for many years after.
Once asparagus reaches maturity, it can produce crops for 15-20 years or more.
You should wait to harvest the asparagus for the first year or two after planting, as the root system needs to conserve energy. Harvesting the shoots and the roots too early or too often can weaken the plant and reduce its overall productivity.
Asparagus is a widely known vegetable grown in gardens and farms worldwide.
With its hardy characteristics, it can grow in many different types of soils and climates. Asparagus is a perennial herbaceous plant that grows 40-60 inches (100-150 cm) tall.
The nutritious vegetable is part of the Asparagacea family that comprises over 2,500 flowering plants. Known for its mild flavor and tender edible shoots that emerge from the ground in early spring.
These shoots are the initial signs of growth and are followed by many more growth stages of development throughout the growing season.
Asparagus is native to regions from Siberia to South Africa and is often grown for ornamental purposes. Asparagus can grow in either an upright or climbing manner and produces discreet flowers that develop into red berries.
The time to grow spears or young shoots which are the edible part of the plant is during the spring months. Asparagus is usually harvested when they are about 6-8 inches (15-20 cm) long and have a tender edible tip.
|Scientific Name||Asparagus officinalis|
|Maturity Size||1-1.5 meters tall|
|USDA Hardiness Zone||4-9|
|Light Requirements||Full Sun to Part Shade|
|Soil||Well-draining soil pH 6.5-7|
Take a look at this time-lapse video of the asparagus growth stages for more insight into its development:
The 7 Asparagus Growing Stages
Growing asparagus may seem like a lengthy task, however, if you dedicate a patch in your garden where the roots can mature, they will need little care.
Let’s look at the details of each asparagus growth stage in more detail, so you know what to expect over the years.
Germination is the first of the asparagus growth stages and will happen 2-3 weeks after planting.
To plant asparagus, you need to prepare the soil first. The soil should be well-drained and rich in organic matter.
Dedicate a spot in your garden that won’t be interfered with for the next few years. After preparing the soil, you can plant asparagus seeds or crowns (root systems of mature plants).
If planting from seed, you can start these indoors several weeks before the last frost date. If growing from crowns, you can grow in spring when the soil has warmed up.
Plant the crowns or seedlings on a trench about 8-12 inches (20-30 cm) deep and space them 18-24 inches (45-60 cm) apart. Spread the roots and cover them with 2 inches (5 cm) of soil.
During the germination stage, ensure the Asparagus seeds are kept moist and planted in a sunny location. Germination happens quicker if the seeds are soaked overnight before planting.
2. Emerging Shoots
The second part of the asparagus growth stage is when the shoots emerge.
Once the seed has germinated, the tiny shoots will surface to the top of the soil. This is the first visible sign of growth for the Asparagus plant.
As the shoots grow, cover them with soil so that only the tips are exposed. It can take around 3-4 weeks for the shoots to emerge after planting, and the time will depend on several factors.
Soil temperature, soil moisture, and the variety of asparagus being grown all contribute to the time frame. Warmer soil and the correct moisture levels speed up the emergence, while cold temperatures and dry conditions slow it down.
Once the shoots emerge, they will continue to grow rapidly and reach their full height of 3-5 feet (1-1.5 meters) within a few months.
3. Crown Formation
After the shoots have emerged and continue to grow, they will form a crown that becomes the main part of the asparagus plant. The crown is where the roots and the shoots will emerge from for the rest of the growing season.
The asparagus crown is the root system underground that produces the shoots and ferns of the asparagus plant.
A mature asparagus crown looks like a small cluster of white or tan-colored roots that can be 2-3 inches (5-7 cm) in diameter. Asparagus roots can spread out to around 6 feet (1.8m) on their own.
The asparagus crowns will produce shoots within a few weeks after planting and continue to grow and make asparagus spears for 15-20 years or more.
4. Foliage Development
Foliage development happens after crown formation on the asparagus plant and will provide the plant with energy from photosynthesis. The foliage helps to shade the soil and keep it cool to reduce evaporation.
The asparagus foliage includes shoots and ferns.
The asparagus plant produces green feathery shoots that resemble long spears. These spears continue to grow and mature into ferns. The ferns of the asparagus are tall and airy, and bright green.
The ferns assist in producing energy and storing food in the root system for the next growing season.
The ferns of asparagus can look quite pretty as a garden backdrop and add height and texture – something to bear in mind when choosing the right location for your asparagus patch.
After the foliage development stage, the asparagus begins to flower.
Flowering happens after the shoots have developed into ferns around 2 to 3 months after the emergence of shoots. Flowering will occur during the spring and early summer months, depending on the climate and region.
The flowers of the asparagus are small yellow-green clusters positioned on the top part of the stem. This time of the asparagus growth stage is essential for seed production.
Asparagus are either male or female. Males usually display more abundant showier flowers, whereas females produce edible spears. The flowers of the asparagus are not edible and are only used for reproduction.
6. Berry Formation
After the flowering time of the asparagus growth stage, small red berries that contain seeds are produced.
The berries are attractive to birds who will happily eat the berries and disperse the seeds around the landscape, so don’t be surprised if you see Asparagus popping out from random places!
After the berries have been produced, they will fall to the ground, and the seeds will germinate the following spring.
You don’t need to do anything to the ground at this point, but if you want to collect a few of the berries, you can store them and plant them in a different location the following season.
The berry formation stage is almost at the final step in its lifecycle. After the berries have dropped, the asparagus plants will prepare themselves for the dormancy stage during the winter.
Stage 7: Dormancy
Dormancy happens when the weather becomes cool in the fall, and the foliage dies. The plant will remain dormant until the following spring, so be sure not to plant anything in the patch until then.
Good practices during this time include cutting back the ferns a few inches above the ground and removing any diseased or yellow leaves to help the plant conserve energy.
As the winter months approach, apply a layer of mulch over the top of the soil. Use shredded leaves or straws to help retain moisture and suppress the weeds.
Keep control of weeds and be careful not to disturb any of the delicate asparagus roots underground.
It is recommended to avoid harvesting asparagus in the first year after planting. Leaving the spears to continue their lifecycle allows them to focus on establishing a healthy root system rather than edible spears.
In most cases, you can begin harvesting in the second or third year after planting, depending on the cultivar and growing conditions.
You can expect to harvest asparagus for 4-6 weeks during the late spring to early summer giving you a great crop to store for the following months.
The shoots are harvested from late spring to early summer before the foliage development stage. As the shoots mature, they become woody and inedible. You will expect to stop picking asparagus in late June or early July.
Asparagus is edible at all stages of its growth cycle but is commonly harvested when the shoots are young and tender. Asparagus needs to be trimmed at the bottom of the spears to avoid a woody dense texture.
As a highly valued and widely enjoyed vegetable, the shoots are used in various dishes that require a sweet earthy flavor.
Asparagus can be boiled, roasted, grilled, sauteed, or used in stew soups or casseroles. These features make Asparagus a versatile vegetable for cooking.
Not only does asparagus provide you with a wide range of cooking options, but it also has some major health benefits! Asparagus is low in calories and carbohydrates and makes a good source of fiber, vitamins, and minerals.
There have been reports that asparagus aids in supporting gut health as well as using its liver-healing properties to ease hangovers! Asparagus is a rich form of folate, a vitamin that helps with blood cell production.
Some people are sensitive to asparagus and can be allergic to its purine levels, a compound that increases uric acid.
If you suffer from allergies to plants of the same family, such as garlic and chives, you may have to pass on asparagus. Otherwise, asparagus has some amazing health benefits and should be added to enhance a balanced diet.
Growing Asparagus Tips & Tricks
Growing asparagus is pretty simple, even for the beginner gardener, but it requires patience.
Here are some tips and tricks to help you grow a successful crop of asparagus:
- Select the right variety. There are several varieties of asparagus available, so make sure you choose one that is most suitable for your growing conditions.
- Plant in well-drained soil. Asparagus thrives in well-drained soil that is rich in nutrients and organic matter. If the soil is too heavy or poorly drained, you can consider planting your asparagus in raised beds. Avoid using sandy and clay soils- these compact over time and will harm the root system.
- Choose the best planting time. Plant asparagus in spring when the soil has warmed up and there is no risk of frost damage. This applies if you are planting seedlings or crowns. Harsh frosts and cold soil will stress the plant’s early life stages.
- Mulch heavily. Apply mulch before the summer months when the ground heats up. Used shredded leaves or straw to help retain the moisture and protect the surface from weeds and soil erosion from watering. Re-apply the mulch just before winter to ensure the underground roots are protected from frost damage.
- Fertilize regularly. Asparagus grows well when fertilized every 4-6 weeks during the growing season. Use a balanced fertilizer such as a 10-10-10 NPK ratio.
Asparagus Seasonality & Growth Times
Asparagus’s seasonality and growth times depend on various factors such as climate cultivar and planting method.
Generally speaking, asparagus is a cool-season crop that is planted in early spring and harvested from late spring to early summer.
In milder climates, asparagus can be planted in the fall for a spring harvest and will grow up to 2 inches (5 cm) per day. Asparagus season can happen as early as late February and continue until June, making the peak months April and May.
Asparagus has a long lifespan and will produce edible spears for 15-20 years or more. The best yields typically occur in the third to the fifth year after planting.
A great rule of thumb is to plant asparagus seedlings (that have been started indoors) or crowns when the soil temperature has risen. When the soil temperature is consistently above 50°F (10°C), it is the best time to start planting.
Best Fertilizer For Asparagus
The best fertilizer for asparagus to flourish is one that is balanced with macronutrients with a ratio of 10-10-10 (10% Nitrogen, 10% Phosphorus, and 10% Potassium).
Apply fertilizer every 4-6 weeks during the growing season and follow the package’s directions.
Avoid using high-nitrogen fertilizers such as chicken manure or blood and bone; this can cause the asparagus to concentrate on foliage growth rather than edible shoots.
You can side-dress the asparagus spears after they have started to emerge. This will maintain the soil fertility and support continued growth.
Unfortunately, asparagus is not a pest-resistant plant, and several problems can affect asparagus growth.
These are the following problems to look out for and how you can combat them:
Asparagus aphids are pale green and powdery; they feed on the leaves of the asparagus and cause stunted growth and death to the infested plants.
You can control asparagus aphids by using organic neem oil solution weekly or by introducing natural predators. Natural predators of asparagus aphids are ladybugs and parasitic wasps.
Beet armyworms are a common pest to asparagus, and they identify as 30 mm soft-bodied caterpillars that are green to black with stripes along their back. In large numbers, they attack the ferns of the asparagus plant and will feed on the foliage.
You can use an organic neem oil solution spray to control beet armyworms on the foliage. Beet armyworms lay eggs in the soil, and by drenching the soil with neem oil solution, you can disrupt the lifecycle and reduce the numbers.
These beetles identify as small black and red beetles that can cause significant damage to the foliage of the asparagus plant.
You can control them by using an insecticidal soap or by picking them off by hand.
Fusarium wilt is a fungal disease that causes the asparagus plant to wilt and die. The spores of the bacteria are in the soil and can be carried through the air.
Unfortunately, there is no cure for Fusarium wilt, and all the plants and soil should be removed and destroyed.
Crown rot is another common fungal disease that is present in the soil and can attack the vascular system of the asparagus spears. It is identified by reddish-brown lesions on the roots and stems and can turn the ferns yellow.
Unfortunately, you cannot treat crown rot with fungicide. The best way to prevent this disease is to keep asparagus free from any stress, such as weeds or drought.
Generally speaking, a fungal infection that occurs on asparagus is less likely in mildly acidic soils. Keep your soil pH above 6.0 and test it yearly using pH test strips that you can find at your local garden store or online.
Using neem oil solution to control pests is safe and effective. Neem oil doesn’t kill the pests immediately but will disrupt their eggs and larvae enough for them to move onto a new location.
To control pests with neem oil, use a spray bottle and mix one teaspoon of neem oil and four drops of dishwashing detergent. Combine these with 1 liter of water and spray once a week.
Continue the application until the numbers have decreased. Neem oil, when undiluted, is very potent and can harm your plants, so be sure to follow the dilution method for safe application.
The dishwashing soap will create a slippery layer over the asparagus, so it is recommended to only apply two weeks before harvesting.
Asparagus Care Guide
Growing asparagus is an effortless task when you have a good understanding of the requirements the plant needs. When given proper care, the plants will produce abundant, high-quality shoots.
Here is a breakdown of the various requirements for asparagus plants:
Asparagus grows best in well-draining soil with a pH level of 6.5 to 7 and is not tolerant to acidity levels above this.
Avoid using heavy clay or sandy soils as these tend to compact over time and cause water to pool. Apply a 2- to 4-inch layer of organic compost to the soil before planting and work it with a fork or trowel.
Ensure the ground is free from weeds, roots, and debris that can potentially affect the root development of the asparagus.
The ideal temperatures for growing asparagus are 75-85°F during the day and night temperatures of 60-70°F.
Sunny days and long growing seasons are preferred for the best results. Temperatures above 86°F or below 55°F can cause root development to slow down and stunt shoot production. Asparagus grows well in zones 4-9.
Some varieties are more prolific in hot temperatures, such as Atlas, Apollo, DE Paoli, and UC 157.
Asparagus needs 8 hours of sun daily. Avoid planting in a place where there are tall trees that can eventually shade the asparagus.
Because the asparagus is long living, you need to think ahead to ensure there are no sun obstructions in the next couple of years. Asparagus can tolerate some indirect sunlight but does best with morning sun and afternoon shade.
Asparagus can grow in a wide range of humidity levels, so there is no need to adjust the moisture in the air. Moderate humidity levels around 50-70% are sufficient for asparagus.
High humidity levels can lead to fungal diseases, and low humidity can cause the plant to dry out. Ensure proper spacing around the plants for air circulation and healthy growth.
Asparagus plants favor moist soil, and you should water them regularly to keep the soil evenly moist. Avoid over-watering them, which will result in the soil becoming waterlogged, causing the roots to rot.
Watering during the harvest season will increase the yields in the dryer months.
Water deeply once or twice a week, depending on your weather conditions. Ensure the soil drains well and there is good air circulation around the plants.
During dry months watering may need to be increased. You can check the top inch of the soil for moisture by sticking your finger in the soil. If your finger comes out clean, then it is time to water.
Asparagus plants benefit from regular fertilization to grow a great crop. Use a balanced slow-release fertilizer with a ratio of 10-10-10 NPK (10% Nitrogen, 10% Phosphorus,10% potassium) or a fertilizer specifically formulated for asparagus.
Apply the fertilizer in early spring before the shoots emerge. Compost or well-rotted manure can amend the soil and provide nutrients.
In the following years, the asparagus plants can be fertilized again in spring with a balanced fertilizer. During the growing season, high nitrogen fertilizer can encourage foliage growth.
However, it’s essential to avoid over-fertilizing as this can cause excessive foliage growth and reduce the plant’s ability to produce spears. Always follow the directions on the packet if you are unsure.
Harvesting Asparagus Spears
The time has arrived when you can start to harvest your first batch of homegrown asparagus.
To ensure you protect the following batch of asparagus, follow these few simple steps on how to harvest.
- Use a sharp, clean knife and cut the spears to the base level.
- Avoid cutting the spears if they are less than the thickness of a pencil.
- Harvest the asparagus spears when they are 6-10 inches tall and ½ inch thick
- Cut before any flowers at the tips begin to open- after this time, the asparagus will become woody and taste bitter.
- Harvest in the morning or early evening when the sun’s rays are not so harsh.
- Avoid harvesting in the first year of growth, as this disturbs the root system and potentially kills the future of the plants.
Asparagus is a nutritious vegetable that is easy to grow. With the right space, care, and attention, your asparagus plants can produce an abundance of high-quality shoots for many years to come.
Asparagus can take a few years to grow and will require a space in your garden that is exclusive to that crop. Other than that, their requirements are similar to many cool-season vegetables, so if you are patient enough, you will be harvesting asparagus for years to come!