In this article, I covered everything you need to know on how to grow asparagus from seed. Growing asparagus can be quite overwhelming as it requires a lot of patience and dedication. Normally, asparagus is grown from bare-root stock crowns because it is observed that it is faster than growing from seed.
Planting from rootstock crowns takes nearly 1 to 3 years to harvest. Cultivating from seed may take longer but, many gardeners choose seed because it is a more worthwhile process. Gardeners have realized that there are numerous benefits of choosing seeds for growing asparagus. Mainly, it is a relatively cheaper option, and seed-grown crops are far less likely to undergo transplant trauma than nursery-grown plants.
A savvy gardener who appreciates the economy of growing asparagus from seed knows that once asparagus starts growing, his garden will produce an abundant crop of spears for another 20 to 30 years.
In northern climates, you can begin seedlings indoors in mid-February or early March. Sow individual seeds in newspaper pots; place the pots where the temperature is about 77ºF. Observe seed sprouting, then lower the temperature to 60 to 70ºF accordingly. After the frost passed away, plant the seedlings 2 to 3 inches deep in a prepared bed. If you notice small flowers, monitor them with a magnifying glass. Categorize the female and male flowers, you will notice female flowers have well-developed, three-lobed pistils and male blossoms are bigger and longer than female flowers. Pluck off all female plants. The subsequent spring, transplant the male flowers to the permanent bed. Asparagus seeds take about three or more weeks to germinate and in about three seasons, asparagus can produce harvestable crops.
The next section will go into details on how to grow asparagus from seed, step by step.
First thing first!
Prepare the Plant Bed
Even before buying the best asparagus seeds, preparation of the plant bed needs to be initiated very carefully as this crop will occupy the same bed for over 30 years or more. Preparation involves a few significant steps to be followed, which can help in finding a good plating spot:
- Even though asparagus can endure partial shade, still prefer to plant asparagus seeds in full sunlight for disease-free plants and harvest.
- Asparagus does best in lighter soils that warm up rapidly in spring and drain well as standing water will quickly decay the roots.
- A simple raised bed is a good choice that’s nearly 4 feet wide by removing all perennial roots and weeds and digging in aged compost (a depth of eight inches).
- Choose the most appropriate spot that remains undisturbed and does not come in the way because the asparagus plant can harvest for nearly 30 years or more.
- Adequate spacing between each seedling needs to be considered.
- Spots with strong winds need to be avoided.
- To curtail the chances of soil-borne disease to your crops, sow the seeds in a part of the garden that has never been cultivated before.
Next, consider having a soil test, this will provide you the vital information on pH and fertilization (the finest pH range for asparagus is 6.5 to 7.0). If some changes need to be done, it’s advisable to do it in the fall before planting, to enable the adjustments to settle in over winter. If this is the case, plant a cool-season cover crop or cover the soil with mulch. Covering the soil with cover crop has its advantages – it protects the soil and also adds valuable organic material into the soil.
Source the Best Quality Seed
After preparing the planting bed, it’s time to choose a suitable seed type from the range of the latest hybrids to cherished heirlooms. Make sure to choose varieties that suit favorably to your growing conditions as this will make cultivation far more smooth and healthy.
Stages of Growing Asparagus [From Seed/Crown to Harvest]
Table of Contents
Varieties of Asparagus Seeds:
Jersey Knight, Jersey Giant, and others in the ‘Jersey’ series are vigorous cultivators that do extremely well in cooler climates and it is resistant to many crop diseases, such as fusarium wilt and crown decay. ‘Jersey Supreme’, the latest early-season grower, is adaptable to sandy soils and disease resistant.
Purple Passion: an extensively grown variety gives a very mesmerizing purple color. Astonishly, when it is cooked, the purple sweet spears change their color to the color green.
Millennium is a consistent cultivator that does well in heavier soils.
Larac is more or less a white French variety.
Apollo is highly disease resistant. And perform greatly in both cool and warm areas.
UC 157 is adjustable to warmer climates and a disease-resistant cultivator.
Atlas gives good disease resistance and grows vigorously in hot weather conditions.
Viking is a flavorful and tender seed type it is also adaptable to colder climates
Mary Washington is a cheap quality heirloom that American growers are using for its traditional appearance, fine flavor, and evenness of its long green stalks. But it normally does not offer heavy cropping.
Precoce D’Argenteuil is an old French heirloom that kept popular for its pale stalks and rose-pink tips. Just like Purple passion variety it also changes its color when cooked. It turns white when blanched.
How to Grow Asparagus from Cuttings
Asparagus Seed Propagation
Now that you know various varieties of asparagus seeds, choosing one type that will suit your growing zone can be an easy task for you. The majority are hardy in zones 3 to 8.
Different varieties of asparagus seeds can be sown based on:
– Hybrid varieties can be sown either in trays or in the ground.
– Heirloom varieties being sensitive to transplanting, suggested being sown into the final planting bed.
– However, in the hot weather, viable seeds can be sown directly into the planting beds.
Follow the below-mentioned process and know the best answer of how to grow asparagus from seed?
Sow asparagus seeds indoors or in a glasshouse for about 8 to 12 weeks before transplanting outside and make sure the risk of frost should have passed. Soil temperature should be between 70 to 85 degrees F.
Soak the seeds for a couple of hours.
Sow the seeds 1/4 to 1/2 inch deep in a sterile seed mix.
Place the pot or tray in a sunny, hot area and keep moistening the soil. You will observe germination of seed after around 14 days (14 to 21 days or longer).
For transplanting, just before a week, harden off the seedlings in fertile soil or cold frame.
Observe the length of the seedlings, once it’s two-inch tall, transplant them into a garden bed with a viable spacing of 12 to 18 inches.
If the soil temperature is at least 60 degrees F, then also asparagus seeds can be directly sowed. Make sure the garden should be weed-free.
And when the soil temperature is 75 degrees F, then you will see seedlings start emerging in 10 to 14 days.
Most importantly, continue giving water, especially during hot and dry periods.
Asparagus Pests and Diseases
Pest/Disease | Type | Symptoms | Prevention |
Cutworms | Insect | 1) Wilting 2) Stems of young spears detached (“cut”) just above the soil line | 1) Observe cutworms and clear them by hand. 2) Remove away weeds and other plant matter. |
Asparagus Beetles | Insect | 1) Spear turns brown and bends in a U shape. 2)Defoliation 3) Damaged seeds/fruits
| 1) Pluck off beetles by hand 2) Dispose of plant matter in the fall where eggs could be making their room. |
Asparagus Rust | Fungus | 1) Pale green spots on newly emerging spears become yellow/orange with concentric circles 2) Reddish-brown blisters emerge in summer, discharging rust-colored spores that turn black; brown ferns 3)Defoliation 4) Lower vigor | 1) Avoid giving excess water to spear or fern. 2) Remove or destroy infected plant matter 3)Choose the best resistant varieties 4)Make sure viable air circulation 5)Do not plant new asparagus nearby |
Fusarium Crown Rot | Fungus | 1)Yellow, stunted, wilted ferns 2)Reddish-brown spots on lower stems, crowns, or roots 3)Rotting spears | 1) Wipeout infected plants 2) Do not plant new asparagus nearby of infected location for another 5 years. 3) Opt resistant varieties 4)Sterilize tools to avoid the spread 5) Avoid overharvesting |
Harvesting Asparagus
- Avoid harvesting during the first harvesting season.
- For young plants, the season may last 2 to 3 weeks. However, developed plants produce longer up to 8 weeks.
- Monitor your plant regularly for harvest-ready spears. Spears grow promptly and may become too woody too soon. The moment an asparagus spear begins to open and have foliage, chewing it becomes a task for you.
- When spears height reaches up to 8 to 10 inches and thickness between 1/2 and 3/4 inch, consider this time to be the best time of harvesting. However, younger, thinner spears are more tender and full of flavor, so depending upon your taste, harvest accordingly.
- To harvest asparagus, use a sharp knife or scissors and just cut the spears at ground level.
- When you observe that the diameter of the spears decreases to the size of a pencil, do not harvest at that time.
- After harvesting, do not forget to fertilize your asparagus in early summer. Use a balanced organic fertilizer on the garden bed, or spread another inch of rich, weed-free fertilizer over the decomposing mulch.
- If you cut down the remaining ferns in summer then you are probably ruining your asparagus bed. Let the ferns grow and mature; this stocks up the nutrients for next year’s spear production. Always leave a minimum of two or three spears on the plant during the growing season.
- If the foliage has died back and turned brown or yellow then only cut back asparagus ferns. This is usually happening in early winter after several touches of frost.
- Use a 1-inch layer of rich, weed-free compost or manure topped with 3 inches of straw to fertilize the garden bed. Also, you can add weed-free mulch or rotted sawdust. In spring, clean spears will start emerging through the mulch.
Storing Asparagus
- A freshly picked asparagus is a flavorful treat in springs. You cannot find such tender asparagus anywhere on store shelves. Although freshly picked up asparagus tastes amazing you can also keep it in the refrigerator for about a week. Put them in a clean plastic bag in the crisper drawer.
- You can freeze asparagus.
- You can also store it in a can but make sure to process it in a pressure canner.
How to Grow Asparagus in a Container [Ultimate Guide]
FAQ: How To Grow Asparagus From Seed
- Should I soak asparagus seeds before planting?
It is highly recommended to soak asparagus seeds for a couple of hours and then sow each seed ½ inch deep in sterile soil, in individual 2-inch pots or trays. Some people prefer to soak asparagus seeds for 48 hours before planting because it helps in speedy germination.
- How long does it take asparagus to grow from seed?
Asparagus takes nearly 21 days or even a longer time to germinate. To harvest from seed, it requires about three years before you get to taste a single spear. So just be patient!
- Is it easy to grow asparagus from seed?
It’s not difficult to grow asparagus from seed; all you have to do is to add an extra year onto the waiting period until you can commence harvesting. But, it needs a lot of space and is a lot of preparation work to get the garden bed ready.
- What is the best time to plant asparagus seed?
Fall (start the process in early spring) is the most ideal time to sow asparagus seed. Plant asparagus seeds in a sunny spot with nutrient-rich, well-drained soil.
- Should I Grow Asparagus in Pots?
Usually, asparagus needs large areas for planting. But some people want it in tight containers; however, there are a few considerations one must take into account. Though planting in pots is a space-saving technique but it will negatively impact the growth and life of the asparagus. You can only expect 2 to 4 seasons of actual asparagus harvests after the establishment period has passed.
Growing Asparagus in Raised Beds [Size, Depth and Plant Spacing]
Conclusion
Indeed, growing asparagus from seeds involves a lot of patience and hard work, although, seed-grown asparagus involves adds up extra up time in harvesting the final crop. Still, most gardeners prefer asparagus seed over the crown for cultivation because the grower’s patience is definitely is rewarded by early-season harvests of asparagus with a flavor that you can hardly find anywhere in the market. You will wish you had planted a bigger asparagus bed!