The Stages of Growing Asparagus You Never Knew Existed

Are you a fan of asparagus spears but clueless about its ferns? Did you know that it can also have edible berries? Delving into the life cycle of asparagus plants can be fascinating and help you easily cultivate them.

Don’t miss out on the joys of growing your own asparagus and watching the plant develop. We’ll provide all the juicy details on the stages of growing asparagus. With this knowledge, you’ll soon be a pro gardener, able to nurture your plants from seed to harvest.

Quick Glance

Scientific Name: Asparagus officinalis
Plant Type:Perrenial
Native Environment:Western Asia & Mediterranean
Growth Rate:Slow growing
Plant Size:Able to reach 7′ tall
Growing Zones:USDA 3-8

The 4 Stages Of Growing Asparagus

The life cycle of asparagus consists of the stages: seed germination, growth, fern, dormancy, and regrowth.

We’ll explore each of the stages of growing asparagus and how it would be planted to provide more context.

Choosing a Site for an Asparagus Patch

asparagus growing in garden

Growing asparagus is a rewarding experience, but it does require some preparation. Therefore, before planting asparagus, you should choose the right growing site. 

Pick a spot with plenty of sunlight and well-draining soil, as asparagus plants don’t do well in areas prone to flooding or that stay wet for long periods of time. 

Pro tip: Don’t forget about asparagus companion plants. A location that could work for multiple plants working together will continue to pay off for many years!

Additionally, ensure the area is large enough to accommodate the asparagus plants (we’ve seen some colossal asparagus ferns!).

Finally, test the soil for pH level, as asparagus prefers slightly acidic soil (pH level of 6.5-7¹). With these steps taken, you can be sure your asparagus will grow healthy and strong! 

Choosing an Asparagus Variety

asparagus plant growing in a field

Before moving on, you want to make sure you choose the best variety for your location and the type of plant. 

Asparagus plants come in male and female forms, each with unique advantages. For example, male plants yield more produce since they do not expend energy producing seeds. 

Conversely, female plants produce seeds that can be used to grow more asparagus the following year. Therefore, combining both male and female plants will ensure enough asparagus for consumption and seed production.

Depending on your preference, you can also choose between colors, such as green or purple asparagus. While they share a similar flavor, the purple variety adds color to your dishes. 

The Jersey Giant variety is ideal for those in northern climates as it can withstand colder temperatures. 

If you want a disease-resistant variety, consider the Jersey Knight, as it is highly resistant to fusarium wilt, crown rot, and asparagus rust.

Soil Preparation, Fertilization & Planting

Growing asparagus requires proper soil preparation and planting for bountiful harvests. To begin, remove weeds and debris from the ground and add compost, aged manure, or other organic material to the soil. 

Weed management is essential, as weeds can invade the entire area if left unchecked. 

If your soil is too acidic, try liming the soil (PDF with lime formula) to reduce the pH level.

Although some gardeners recommend applying salt to your asparagus bed, avoid doing this, as salt can seriously damage soil quality. Instead, add phosphorus-rich amendments such as bone meal, composted manure, or rock phosphate. 

High nitrogen fertilizer should be avoided as it can cause excessive foliage growth and reduce the plant’s ability to produce spears. 

Preparing The Planting Area

You can plant asparagus in raised beds or containers, ensuring adequate drainage. Check out our raised garden bed ideas page for more info. But asparagus will typically do better in the ground. 

Time of Planting

Asparagus is a cool-season crop that can be planted in early spring and harvested from late spring to early summer when the soil temperature has risen to at least 50 degrees Fahrenheit.

The best time to plant asparagus varies depending on the climate, as asparagus can be grown in fall or early winter in mild climates and in early spring in cold climates. 

Now that the site and soil are prepared, it’s time to start thinking about planting.

You can plant your asparagus during the fall or early winter if you reside in a warmer climate, such as the southern Florida region.

Planting

You can plant your asparagus bed with either asparagus seeds or crowns. However, for novice gardeners, it is recommended to plant crowns instead.

Why, you ask? Crowns are a year old and already have a developed root system, significantly reducing the wait time for your asparagus to flourish. 

So, if you’re looking for a quicker and more convenient way to grow your asparagus, planting crowns is the way to go!

Using Asparagus Crowns for Planting

You can purchase crowns online or in stores, but they might be dry. However, don’t worry! Soak them in water for a few hours to bring them back to life.

To plant your asparagus crowns:

  1. Dig trenches that are six inches deep and eight inches wide.
  2. Place the roots inside and cover them with soil.
  3. Space the asparagus approximately 1.5 feet apart, and space the rows 3-6 feet apart.
  4. Give them a good watering until the soil is no longer rapidly absorbing water.
  5. Add a layer of mulch made from grass clippings or wood chips to help preserve moisture, reduce weed growth, and deter pests. Be sure to make the layer 6-8 inches deep.

An alternative planting technique is to gradually cover the asparagus crowns. Simply cover the newly planted crowns with a few inches of soil and repeat the process every 2-3 weeks. 

Both methods are effective, so choose the one that best suits your gardening style.

Planting Using Asparagus Seeds

Before planting your asparagus seeds, soak them in water for two days to help with germination. If you live in a colder region, start the seeds indoors and transplant them outside once the danger of frost has passed and the soil temperature has reached at least 50°F.

When planting asparagus from seed, sow seeds 1/2 inches deep, 4-5 inches apart. 

Once planted, asparagus should be watered regularly to keep the soil evenly moist, but avoid over-watering as this can damage root systems. 

1.) Seed Germination

After planting your asparagus seeds, the next step in the growth process is seed germination. It’s important to note that this process can take some time, typically two to eight weeks.

While you might not see any visible growth immediately, the seed is working to develop the asparagus roots below the surface. As the seed opens, the roots begin to form and grow in search of water and nutrients.

It’s essential to keep the soil moist during this stage, as dry soil can hinder germination and stunt the growth of the asparagus roots. 

Patience is critical during this time, but with proper care and attention, your asparagus seeds will begin to thrive and grow into healthy plants.

2.) Growth Begins

As the asparagus crown develops and the roots grow, the plant will produce shoots that emerge from the soil, marking the beginning of its growth phase.

When the shoots first appear, the growth of the asparagus plant accelerates. This is because the foliage starts to photosynthesize, allowing the plant to produce food and energy. 

This growth phase is crucial for developing the asparagus plant and its ability to produce healthy and delicious asparagus spears.

3.) Ferning Out

asparagus in the fern growing stage

Ferning out is the next stage of asparagus plant growth. During ferning out, asparagus has evolved a stage where it can bear flowers and thus produce seeds. 

This vital stage of asparagus plant development is characterized by the formation of seed pods in the early stages of the plant’s life cycle. 

These seed pods contain seeds that will eventually grow into new asparagus plants. In addition, the fern-shaped leaves of asparagus plants during ferning out promote growth through photosynthesis and produce extra energy for the plant to use during this critical growth stage.

Harvesting asparagus during its earliest growth cycle is not recommended as it may result in reduced yields and lower quality asparagus harvest. Instead, harvesting asparagus at full maturity is best, as it allows the plant to fully develop and put all its resources towards growing new asparagus plants instead of seed production. 

The fern-shaped leaves of asparagus plants during ferning out are an essential indicator of plant health and should be a goal during the first couple of years of growth. 

4.) Dormancy Begins

Asparagus enters a state of dormancy during the winter months. During this time, the asparagus plant stops producing new leaves and stems but is still alive and requires minimal watering and light exposure to stay healthy. 

When the leaves turn yellow and die off. This means photosynthesis stops, and the plant relies on stored energy in the crown to survive the winter.

However, the dead foliage can provide a hiding place for asparagus beetles to overwinter, harming the following year’s crop. In addition, asparagus beetles can cause damage to the ferns, which can result in reduced yield and quality of the asparagus spears.

Removing any dead foliage before winter sets in is essential to prevent this. You can cut the dead leaves and compost them. This will not harm the plant and will help reduce the population of overwintering pests.

Adding some protection from frost is also a good idea to ensure the dormant stage is successful.

The dormant stage can last six to twelve weeks, depending on the variety of asparagus plants being grown and the USDA climate zone.

5.) Regrowth

Asparagus plants begin to stir from dormancy once spring arrives, and the spears become firmer. To boost your plants, you can add a top dressing of compost or other fertilizer in early spring during the second year. 

This added nutrition will help your plants become stronger, which leads to a more significant yield of delicious asparagus spears in the following growing season.

Harvesting

harvest of asparagus

One of the hardest things about planting asparagus is resisting the urge to harvest your crop the first year after planting. Asparagus plants require two to three years to form deep roots. The strength of these roots is vital to cultivating a prolific and long-lasting asparagus patch. 

Suppose your crop produces well the second year after planting. In that case, you can harvest a few spears (about 25% of your crop) so long as the stalks you harvest are at least five inches tall (Harvest when spears are 5-7 inches high, any higher, and your asparagus will be tough and stringy). 

Don’t worry – once you’ve made it to the third year after planting, you can begin to harvest yearly. 

Asparagus should be harvested in late spring to early summer.

If the days are warm, you’ll want to harvest every two to three days. You can use a sharp knife or simply snap them off with your hands. 

Harvesting asparagus too early or often can weaken the plant and reduce yields. Average yields of asparagus are between 4 and 12 pounds per plant, depending on growing conditions such as soil type and temperature. 

However, asparagus plants can take 10 years or more to reach their full harvest potential.

Finally, check for any signs of wilting, such as yellowing or browning of spear tips, before harvesting them. Finally, note that harvest timing varies seasonally with varying growing conditions. 

So, it’s best to consult local growers or agricultural experts for more information on asparagus growing stages and harvest timing.

Video for Growing Asparagus

Here is a video showing some growing tips:

FAQ

How Long Does It Take For Asparagus To Grow?

Asparagus plants take about two years to establish themselves fully. Then, in the third year, you can start to harvest. While this sounds like a long time to harvest, this perennial will continue to grow for decades if properly cared for.

What Does Asparagus Look Like When it is Ready?

When asparagus spears are ready for harvesting, they are 5 to 7 inches tall and have a diameter slightly more significant than a pencil. This is when they are at their peak and should be cut as soon as they are ready.
 
If you notice that the spears’ diameter gets as small as a pencil or smaller, it’s time to stop harvesting as it may not be growing vigorously anymore. 

Does Asparagus Regrow After Cutting?

The shoot you cut off will not grow into another spear; other shoots will emerge and grow into spears to harvest.

What Happens If You Let Asparagus Grow And Don’t Harvest?

Harvesting asparagus is not mandatory, and you can leave the spears to grow into tall fern-like plants. However, if you don’t harvest your asparagus, the plant will continue to grow and eventually produce berries.

While the berries are edible but less commonly consumed than the asparagus spears, allowing the plant to produce berries can reduce the plant’s energy directed toward spear production. 

Additionally, harvesting asparagus can help maintain the plant’s health by preventing overcrowding and reducing the likelihood of pests and disease.

References

1: https://web.ics.purdue.edu/~drhodes/hort410/aspara/as00001.htm. (n.d.). https://web.ics.purdue.edu/~drhodes/hort410/aspara/as00001.htm

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Davin is a jack-of-all-trades but has professional training and experience in various home and garden subjects. He leans on other experts when needed and edits and fact-checks all articles.