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How to Grow Asparagus From Seed: a Complete Guide (2023)

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grow asparagus from seedYou’ve likely seen asparagus at the market and dreamed of harvesting those tender spears fresh from your backyard. But starting asparagus from seed can seem daunting. No worries – you’ve got this. Be patient, provide good drainage and sunlight, and in a couple of years, you’ll be snacking on homegrown asparagus.

Choose disease-resistant varieties like Argenteuil or UC-157. Sow indoors 10-12 weeks before your last frost, then transplant seedlings when the soil reaches 50°F. Space plants 18 inches apart in sunny rows 5-6 feet wide. Let spearheads develop into ferns the first two seasons while roots establish.

By year three, you can start harvesting for 6-10 weeks when spears reach 6-8 inches tall. Keep picking promptly so plants keep producing. Follow these tips, and soon you’ll be enjoying the sweet crunch of just-picked asparagus.

Key Takeaways

  • Start seeds indoors 10-12 weeks before the first frost.
  • Transplant seedlings when the soil is 50°F, spacing them 18 inches apart in sunny rows that are 5-6 feet wide.
  • Allow the ferns to grow during the first 2 seasons to establish roots.
  • Promptly pick 6-8 spears during the 6-10 week harvest window.

Starting Asparagus

Starting Asparagus
Start indoors Feb-May at 70-85° by soaking seeds for 2 hours, then planting them 1⁄2 deep in sterile soil. In 2-8 weeks, you’ll see sprouts emerge for later transplanting. Select hybrid varieties for yield and disease resistance.

Use grow lights or a southern window for 16-hour days. Thin seedlings to 2 inches apart. Slowly introduce them to sun and wind before planting out. Let ryegrass grow nearby to suppress weeds without competing roots.

Plant annuals like carrots between rows. Care for those seedlings with warmth, light, and moisture for robust transplants. Space and transplant properly for fat spears. With good germination technique, you’ll reap an asparagus harvest for 15+ years.

To Plant

To Plant
Soak those seeds a few hours before planting ’em 1/2 inch deep in sterile soil. Preparation is key for asparagus from seed. Till that area to loosen the earth and mix in rich compost – asparagus are heavy feeders that need nutrition from the start.

Rake the bed smooth and sow seeds 1/2 inch deep and 1-2 inches apart in rows or blocks. Lightly cover and keep consistently moist, not soggy, as seeds germinate over 2-8 weeks. Shelter emerging sprouts if frost threatens and thin to 4 inches apart once established.

Let seedlings strengthen through summer before transplanting outdoors in fall at least 6 weeks before your first frost date. Space 1 foot apart in loose, fertile soil in full sun. Mulch well and continue feeding your young plants next spring for roots to mature before harvest.

To Grow

To Grow
You silly goose, transplant your precious sprouts after 10-12 weeks indoors at 70-85F before the last frost arrives, lest you desire woefully wilted weeds!

Check moisture levels every 2 weeks at your seedlings before transplanting.

Give them room to reach their full potential by using proper density spacings.

Allow water to fully run off after irrigating to prevent waterlogged roots.

Test and amend the soil so your asparagus will thrive with all the nutrients they need.

With care and patience, those tiny seeds will transform into a bountiful perennial harvest for years to come.

A little effort now yields great rewards later when you grow asparagus from seed.

To Harvest

To Harvest
You’ve nurtured your asparagus from seed to harvestable fronds. Now it’s time to reap the rewards! As spear tips emerge from the soil in spring, snap off the first flush at ground level when spears are 6-10 inches tall.

Use a sharp knife or specialized asparagus knife. Harvest lightly the first two years, then more fully in year three. Pick daily during the 6-8 week harvest window when weather is warm to maximize quantity and quality.

Lift tall fronds lightly to find spears buried below. Store freshly cut spears upright in water in the fridge.

What Asparagus Craves

What Asparagus Craves
Gotta amend that soil with nitrogen for those hungry spears you’re sprouting. Asparagus craves nutrients – feed that bed compost and manure before planting.

Plant companion crops like beans, parsley, and tomatoes in between the spears to fix nitrogen. Top dress with fresh compost or grass clippings as mulch. Let it decompose into organic matter to balance the pH.

Test the soil yearly and add amendments like lime to maintain ideal conditions. Fertilize lightly with organic sources, never too much.

Be patient, harvest lightly the first seasons as the crowns mature. They’ll reward you with abundant, sweet spears for decades to come.

Where to Buy Asparagus Seeds and Roots

Where to Buy Asparagus Seeds and Roots
We’ve got plenty of asparagus seed options from both catalogs and garden centers.

  1. Jersey Knight F1 – disease-resistant hybrid from Johnny’s Seeds
  2. Purple Passion – heirloom with purple spears
  3. Millennium – high-yielding male hybrid
  4. UC 157 F1 – high yield, rust resistance from Burpee
  5. Atlas – all-male hybrid, thick spears

Quality asparagus starts with vigorous crowns or certified disease-free seed. Choose varieties bred for your region and needs, like higher yields or disease resistance.

Whether packing bare roots from a nursery or collecting seeds from the garden, start planning next season’s patch this winter. The investment in patience will pay off for years to come once those heavenly spears emerge.

Common Pests and Diseases: Asparagus

Common Pests and Diseases: Asparagus
When searching for your green oasis, watch for the thieves that silently steal nurturance. Common asparagus pests and diseases can plague your crop, but proactive prevention and organic solutions will help you harvest a bountiful yield.

Here are some tips for recognizing and controlling the most common culprits:

Pest/Disease: Asparagus beetle

Identification: Shiny blue-black beetles and grey, spiny larvae

Organic Control: Hand pick, trap crops, neem oil

Pest/Disease: Asparagus aphid

Identification: Greenish-black soft bodies on spears and ferns

Organic Control: Insecticidal soap, ladybugs

Pest/Disease: Fusarium wilt

Identification: Wilting ferns, rotting crowns

Organic Control: Improve drainage, avoid injury, solarize soil

Pest/Disease: Crown rot

Identification: Brown, mushy crowns

Organic Control: Rotate planting, avoid overcrowding

With vigilance and integrated pest management, you can maintain healthy asparagus that delivers delicious spears for years to come. Growing the perennial from seed allows you to select resistant varieties adapted to your good growing conditions.

The Anatomy of an Asparagus Plant

The Anatomy of an Asparagus Plant
Let’s see the roots, stems, and feathery fronds of that asparagus arise when you nurture the seed.

  • Plant seeds 1/2 inch deep in loamy soil. They will sprout skinny stalks in 2-4 weeks.
  • Fertilize and water seedlings regularly for healthy growth.
  • Transplant outdoors when stalks reach 4-6 inches. Give each plant 18 inches of growing room.

Position plants to maximize sunlight for photosynthesis. Group with carrot and parsley to repel pests. The roots will strengthen, shoots will thicken. Soon you’ll enjoy a bountiful harvest of tasty spears.

How to Divide Asparagus

How to Divide Asparagus
You’ll want to divide dormant asparagus crowns in late winter before spears emerge to reset the harvest clock.

  • Dig and lift root balls carefully to minimize damage.
  • Replant crowns 18-24 inches apart and 5-6 inches deep.
  • Cover with 2 inches of soil, fill in as spears grow.

Dividing asparagus crowns when plants are dormant allows you to propagate new plants and stimulate productivity in older crowns. Carefully separating and replanting the root balls in early spring ensures plants are established before summer heat.

Proper plant depth and spacing maximizes fertility, while avoiding self-seeding that can reduce spear size and quality. Take time in late winter to divide your asparagus patch and enjoy an abundant harvest for years to come.

Frequently Asked Questions (FAQs)

What varieties of asparagus grow best in my hardiness zone?

Jersey Giant and Jersey Knight are excellent heirloom varieties adapted to colder regions. Purple Passion offers unique purple spears and thrives in most zones. For warmer regions, try UC-157 F1 hybrid or Atlas for high yields and disease resistance.

Focus on disease-resistant, high-yielding hybrids or heirlooms suited to your climate.

How do I know when my asparagus crowns are ready to harvest?

You can start harvesting asparagus crowns in the third spring after planting when the spears reach a pencil thickness.

How long does an asparagus bed last before I need to replant?

An asparagus bed will last 15+ years before needing replanting if you care for it properly. Select disease-resistant varieties, fertilize yearly, control pests, divide crowns every few years, and cut ferns back each fall to keep your asparagus patch vigorous and productive for over a decade.

Can I grow asparagus in containers?

Yes, you can grow asparagus in containers. Choose deep pots, at least 12 inches, with drainage holes. Use a quality potting mix and fertilize regularly. Site containers in full sun. Crowns planted in pots produce spears for about 4 years before replanting.

What companion plants help deter asparagus beetles?

Intersperse onions, garlic, and marigolds around the asparagus bed. Their strong scents can mask the asparagus from beetles. You could also try companion planting with tomatoes. Their odor repels the beetles while attracting beneficial insects.

Conclusion

You’ve now learned everything you need to successfully grow asparagus from seed. By starting seeds indoors and transplanting the seedlings at the right time, you can grow your own asparagus bed. Give your asparagus what it craves – full sun, fertile soil, adequate water, and nutrients – and you’ll be rewarded with years of abundant spears to harvest.

The effort to establish an asparagus patch truly pays off in the long run. With proper care, your homegrown asparagus from seed will continue producing for over a decade.

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Mutasim Sweileh

Mutasim is a published author and software engineer and agriculture expert from the US. To date, he has helped thousands of people make their yards lush and thick.