Asparagus is great to have in a spring garden, and once established, the plants can produce enough spears for weeks of fresh eating! You might be surprised to learn that you can get asparagus in colors other than green, and that you can find all-male plants that produce more spears.
So, what is the best asparagus to grow? The best asparagus varieties to grow are: Conovers Colossal, Erasmus, Grande Hybrid, Jersey Giant, Jersey Knight, Jersey Supreme, Mary Washington, Millenium, Purple Passion, & Spartacus. Some of these have purple spears, but most are green. Some are all-male varieties that produce lots of spears.
Of course, most of these asparagus varieties are hardy to Zone 3 (down to -40 degrees Fahrenheit or -40 degrees Celsius). Some of them are heat tolerant so the spears will resist becoming tough and ferning in summer.
In this article, we’ll take a closer look at these 10 asparagus varieties. We’ll also answer some common questions about asparagus plants.
Let’s begin.
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10 Best Asparagus Varieties To Grow
Some asparagus varieties are purple, giving you a dazzling alternative to the green you might be more familiar with. Others are all-male, meaning they won’t produce berries – but they will produce more spears than female plants!
Here are 10 asparagus varieties that you should consider growing:
- Conovers Colossal – this green heirloom asparagus variety dates back to the 19th century. S.B. Conover of New York City developed it in the American Civil War era. The crowns produce a heavy yield of large green spears. You can learn more about Conovers Colossal asparagus from Baker Creek Heirloom Seeds. (Note: these are sold as seeds, not as crowns).
- Erasmus – this purple asparagus variety is all-male, giving the plant spears with a brilliant color and the ability to produce lots of spears. It is hardy in Zones 3 to 10 (as cold as -40 degrees Fahrenheit or -40 degrees Celsius). You can learn more about Erasmus asparagus from Gurney’s. (Note: these are sold as seeds, not as crowns).
- Grande Hybrid – this green asparagus variety is both disease-resistant and heat-tolerant, giving the plant a chance to produce plenty of medium-large spears before they become tough and start to fern. It is hardy in Zones 3 to 8 (as cold as -40 degrees Fahrenheit or -40 degrees Celsius). You can learn more about Grande Hybrid asparagus from Gurney’s. (Note: these are sold as plugs, not as crowns).
- Jersey Giant – this green hybrid asparagus variety has good disease resistance and is mostly male, but the plants are not heat-tolerant, so you may need to harvest when the spears are a bit shorter to avoid tough spears and ferning. It is hardy in Zones 3 to 9 (as cold as -40 degrees Fahrenheit or -40 degrees Celsius). You can learn more about Jersey Giant asparagus from Gurney’s. (Note: these are sold as crowns).
- Jersey Knight – this green asparagus variety is mostly male. The plants are heat tolerant, meaning they can send up lots of large spears before they become tough and start to fern. It is hardy in Zones 3 to 10 (as cold as -40 degrees Fahrenheit or -40 degrees Celsius). You can learn more about Jersey Knight asparagus from Stark Brothers.
- Jersey Supreme – this green asparagus variety is all male and disease resistant. The plants produce early in the season so you can get spears sooner than you could from other varieties. It is hardy in Zones 3 to 8 (as cold as -40 degrees Fahrenheit or -40 degrees Celsius). You can learn more about Jersey Supreme asparagus from Stark Brothers. (you can order medium, giant, or heavy grade plants).
- Mary Washington – this green asparagus variety produces high yields. It is hardy in Zones 4 to 9 (as cold as -30 degrees Fahrenheit or -34 degrees Celsius). You can learn more about Mary Washington asparagus from Eden Brothers. (seeds come in a packet of 2 grams, which is about 56 seeds.
- Millenium – this green asparagus variety was developed by Professor David Wolyn at the University of Guelph in Canada. The plants are productive and adapted to a wide range of soil types. It is hardy in Zones 3 to 8 (as cold as -40 degrees Fahrenheit or -40 degrees Celsius). You can learn more about Millenium asparagus from Nourse Farms. (Note: these are sold as 1-year roots).
- Purple Passion – this purple asparagus variety is mostly all-male. The plants are heat tolerant so that you can get plenty of spears before the summer causes tough spears and ferning. It is hardy in Zones 3 to 10 (as cold as -40 degrees Fahrenheit or -40 degrees Celsius). You can learn more about Purple Passion asparagus from Stark Brothers.
- Spartacus – this green hybrid asparagus variety is all-male. The plants are high-yielding so that you get lots of long, straight, medium-size spears. It is hardy in Zones 3 to 8 (as cold as -40 degrees Fahrenheit or -40 degrees Celsius). You can learn more about Spartacus asparagus from Gurney’s.
The table below summarizes these varieties by color and USDA Hardiness Zones (you can find your local hardiness zone with this map).
Asparagus Variety | Spear Color | Cold Hardy Zone |
---|---|---|
Conovers Colossal | green | unknown |
Erasmus | purple | 3-10 |
Grande Hybrid | green | 3-8 |
Jersey Giant | green | 3-9 |
Jersey Knight | green | 3-10 |
Jersey Supreme | green | 3-8 |
Mary Washington | green | 4-9 |
Millenium | green | 3-8 |
Purple Passion | purple | 3-10 |
Spartacus | green | 3-8 |
by color and USDA Hardiness Zones
Here are some answers common questions about asparagus plants.
When Does Asparagus Grow?
Asparagus spears begin to grow from the crown early in the spring. This happens when soil temperatures get to about 50 degrees Fahrenheit (10 degrees Celsius).
The spears continue to grow throughout the spring and summer. Asparagus spears only stop growing in fall after frost kills them.
Usually, you harvest asparagus during late spring, in May and into June. After that, the spears become tough and fibrous as they start to “fern out”.
You can learn more about when asparagus grows in my article here.
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How Big Do Asparagus Plants Get?
Asparagus spears can as tall as 7 feet (2.1 meters) high. However, you will usually harvest the spears for eating long before then.
A good guideline is to cut asparagus spears for eating when they reach a height of 6 to 10 inches (15.2 to 25.4 centimeters). You should cut spears before they start to look like ferns, since they will become tough after they start to fern out.
An asparagus plant’s ferns (above ground) have a width of 2 to 3 feet (61 to 91 centimeters). The crown and root system can grow to a diameter of 6 feet (1.8 meters) in diameter.
You can learn more about how big asparagus plants get in my article here.
Does Asparagus Spread?
Asparagus will spread as it grows. Asparagus roots are capable of spreading out to a distance of 6 feet (1.8 meters) from the crown.
Asparagus ferns (which are mature spears that have produced foliage) can reach a width of 3 feet (90 centimeters) above ground. As asparagus plants age, they will send up more spears, since it has a larger crown and larger energy reserves.
You can learn more about how asparagus spreads in my article here.
Note: asparagus can also spread by their red berries.
What Are The Red Berries On My Asparagus Plants?
The red berries you see on your asparagus plant are pods that contain several seeds. Normally, only female asparagus plants produce these red berries or seed pods.
However, male plants must also be present for the seed pods to appear. If you want to propagate asparagus, you can collect seeds from the berries, dry them out, and plant them to get more crowns.
Why Are My Asparagus Plants Falling Over?
Asparagus plants will often fall over once they mature. This usually happens in late fall, after the spears have grown several feet tall and “ferned out”.
A frost can also kill asparagus spears to end the growing season, causing them to tip over. Pests (such as cutworms) may do damage that can make asparagus spears to grow crooked or fall over.
You can learn more about why asparagus plants fall over (and how to prevent it) in my article here.
Conclusion
Now you know about different asparagus varieties and their benefits.
I hope you found this article helpful. If so, please share it with someone who can use the information.
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~Jonathon