How to Grow Globe Artichokes from Seed

Embarking on the Artichoke Adventure: Growing Globe Artichokes from Seed

The globe artichoke (Cynara cardunculus var. scolymus) is a truly magnificent vegetable, both for its striking architectural form and its delectable, buttery heart. While many gardeners opt for purchasing established plants, successfully growing globe artichokes from seed offers a rewarding and often more economical route to enjoying this gourmet delicacy. This comprehensive guide will walk you through every essential step, from selecting the right seeds to harvesting your homegrown treasures.

Understanding the Globe Artichoke Lifecycle

Globe artichokes are tender perennials in their native Mediterranean climates, but in many temperate regions, they are treated as annuals or biennials. This means they typically complete their life cycle within one or two years. Understanding this is crucial for successful seed starting. Artichokes have a long growing season, so starting seeds indoors several weeks before the last frost is paramount.

Choosing the Right Globe Artichoke Varieties for Seed Starting

Not all globe artichoke varieties are equally suited for seed propagation. Some heirloom varieties are notoriously difficult to grow true from seed, meaning the resulting plants may not resemble the parent. For reliable seed-to-harvest results, focus on modern hybrids specifically bred for seed-grown production.

Popular Seed-Propagated Varieties:

• ‘Imperial Star’: This is a widely recommended variety for seed starting. It’s known for its early maturity and consistent performance, often producing edible buds in the first year.
• ‘Green Globe’: While ‘Green Globe’ is also available as plants, selecting seeds from reputable suppliers can yield good results. It’s a classic choice with excellent flavor.
• ‘Opera’: Another hybrid that is generally reliable from seed, offering good yields and disease resistance.

Key Considerations Before You Begin

Before sowing those precious seeds, a little planning will go a long way towards ensuring your artichoke-growing success.

Soil and Site Selection: The Foundation of Success

Globe artichokes thrive in fertile, well-drained soil. They prefer a slightly acidic to neutral pH (6.0-7.0).

• Sunlight: Artichokes are sun-worshippers. Choose a location that receives at least 6-8 hours of direct sunlight per day.
• Soil Preparation: Amend your planting area generously with organic matter, such as compost or well-rotted manure. This will improve drainage and provide essential nutrients. Raised beds are an excellent option if your soil tends to be heavy or waterlogged.
• Wind Protection: While not strictly essential, young artichoke plants can be susceptible to wind damage. Consider planting them in a location with some natural windbreak or providing temporary protection.

Starting Your Globe Artichoke Seeds Indoors: A Step-by-Step Approach

The journey from tiny seed to majestic artichoke plant begins indoors, typically 8-12 weeks before your last expected frost date.

Step 1: Gathering Your Supplies

1. Seeds: Choose high-quality seeds of a reliable hybrid variety.
2. Seed Starting Mix: Use a sterile, lightweight seed-starting mix. Avoid heavy garden soil, which can compact and hinder germination.
3. Seed Starting Trays or Pots: Small cell packs, peat pots, or biodegradable pots are ideal. Ensure they have drainage holes.
4. Watering Can or Spray Bottle: For gentle watering.
5. Heat Mat (Optional but Recommended): Artichoke seeds germinate best in warm soil.
6. Clear Plastic Dome or Wrap: To maintain humidity.

Step 2: Sowing the Seeds

• Fill your chosen containers with moist seed-starting mix.
• Sow 2-3 seeds per cell or pot, about ¼ inch deep.
• Gently water the soil surface to ensure good seed-to-soil contact.
• Cover the trays or pots with a clear plastic dome or plastic wrap to create a humid environment.

Step 3: Providing Optimal Germination Conditions

• Temperature: Aim for a soil temperature of 70-75°F (21-24°C). A heat mat placed under the trays will help maintain this consistently.
• Light: Seeds do not require light to germinate, but once seedlings emerge, they will need ample light.
• Moisture: Keep the seed-starting mix consistently moist but not waterlogged.

Step 4: Caring for Your Seedlings

• Once seedlings emerge (typically within 7-14 days), remove the plastic cover to improve air circulation and prevent damping-off disease.
• Light: Provide strong, bright light for 14-16 hours per day. A grow light positioned a few inches above the seedlings is highly recommended to prevent them from becoming leggy.
• Watering: Water when the top ¼ inch of soil feels dry. Water from the bottom if possible to encourage root growth and prevent splashing soil onto the leaves.
• Fertilizing: Once the seedlings have developed their first true leaves, you can begin feeding them with a diluted, balanced liquid fertilizer (half-strength) every 2-3 weeks.
• Thinning: If multiple seeds germinated in a single cell, thin to the strongest seedling by snipping the weaker ones at the soil line with clean scissors.

Hardening Off Your Artichoke Plants: Preparing for the Great Outdoors

Before transplanting your tender seedlings into the garden, it’s crucial to gradually acclimate them to outdoor conditions. This process, known as “hardening off,” prevents transplant shock.

The Hardening Off Process:

• About 7-10 days before your last frost date, begin by placing the seedlings in a sheltered, shaded outdoor location for a few hours.
• Each day, gradually increase the duration and exposure to direct sunlight.
• Bring them indoors if temperatures drop significantly or if strong winds are present.
• Continue this process until the seedlings are accustomed to spending a full day and night outdoors without any adverse effects.

Transplanting Globe Artichokes into the Garden

Once the danger of frost has passed and your seedlings are hardened off, it’s time to move them to their permanent garden home.

Timing is Key:

• Transplant after all danger of frost has passed in your region.
• The soil temperature should be at least 50°F (10°C).

Planting Technique:

• Dig planting holes that are twice as wide and just as deep as the seedling’s root ball.
• Space plants at least 3-4 feet apart, as artichokes can grow quite large.
• Gently remove the seedling from its pot, taking care not to disturb the roots. If the roots are tightly bound (root-bound), gently loosen them.
• Place the seedling in the hole, ensuring the top of the root ball is level with the surrounding soil. For slightly taller seedlings, you can plant them a little deeper, burying the stem up to the lowest leaves.
• Backfill the hole with soil, firming gently around the base of the plant.
• Water thoroughly after transplanting to settle the soil and reduce transplant shock.
• Apply a layer of mulch around the base of each plant to help retain moisture, suppress weeds, and regulate soil temperature.

Ongoing Care for Thriving Artichoke Plants

With your artichokes successfully transplanted, consistent care will ensure abundant harvests.

Watering: The Thirst of the Artichoke

Artichokes are thirsty plants, especially during hot, dry periods and when buds are developing.

• Water deeply and consistently, aiming to keep the soil evenly moist but not soggy.
• Check soil moisture regularly by sticking your finger a few inches into the ground.
• Drip irrigation or soaker hoses are excellent for delivering water directly to the root zone and minimizing water on the leaves, which can help prevent fungal diseases.

Fertilizing: Feeding Your Giants

Artichokes are heavy feeders and benefit from regular nutrient replenishment.

• Apply a balanced, all-purpose fertilizer (e.g., 10-10-10) in early spring when new growth appears.
• Follow up with a side dressing of compost or a nitrogen-rich fertilizer once the first buds begin to form.
• Avoid over-fertilizing with nitrogen, as this can lead to lush foliage at the expense of bud production.

Weeding: Keeping Competitors at Bay

Weeds compete with your artichokes for water, nutrients, and sunlight.

• Keep the area around your artichoke plants free of weeds, especially during their early growth stages.
• Mulching heavily will significantly reduce weed pressure.
• When hand-weeding, be careful not to disturb the shallow root system of the artichoke plants.

Pest and Disease Management: A Proactive Approach

While generally robust, artichokes can be susceptible to a few common pests and diseases.

• Aphids: These small insects can cluster on new growth and buds. A strong spray of water, insecticidal soap, or neem oil can effectively control them.
• Slugs and Snails: These slimy creatures can chew holes in leaves and buds. Use slug bait (eco-friendly options are available) or place beer traps around your plants.
• Artichoke Plume Moth: The larvae of this moth can bore into the buds. Inspect your plants regularly and remove any infested buds. Row covers can help prevent adult moths from laying eggs.
• Fungal Diseases: Good air circulation, proper watering (avoid overhead watering), and prompt removal of affected leaves can help prevent diseases like powdery mildew.

Harvesting Your Prize: When and How to Pick Artichokes

The most exciting part of growing artichokes is harvesting the delicious buds.

Signs of Readiness:

• Artichoke buds are ready to harvest when they are firm, plump, and the bracts (leaf-like scales) are tightly closed.
• The size of the bud will depend on the variety, but generally, they are harvested when they reach about 3-5 inches in diameter.
• The most desirable part is the unopened flower bud. If the bracts start to open, the bud is becoming too mature for eating as a bud, though it will still produce a lovely purple flower.

Harvesting Technique:

• Use a sharp knife or strong pruning shears to cut the stem about 1-2 inches below the bud.
• It’s best to harvest in the morning when the plant is cool and the buds are firmest.
• Leaving a small piece of stem attached to the bud can help it stay fresh longer.

Successive Harvests:

• After harvesting the main terminal bud, the plant will often produce smaller side shoots or lateral buds. Continue to harvest these as they mature.
• Allowing some buds to fully open will attract pollinators and can result in beautiful purple flowers.

Overwintering Your Artichoke Plants (in Suitable Climates)

In regions with mild winters (USDA hardiness zones 7-10), globe artichokes can be perennial. Proper overwintering practices will ensure your plants return year after year.

Overwintering Steps:

• In late autumn, after the last harvest and before the first hard frost, cut back the foliage to about 6-12 inches from the ground.
• Mulch heavily around the base of the plants with a thick layer of straw, hay, or compost (4-6 inches).
• In colder zones within the perennial range, you can also wrap the remaining stalks with burlap or a frost blanket for added protection.
• Remove the mulch and dead foliage in early spring as new growth begins to emerge.

Troubleshooting Common Issues

Even with the best care, you might encounter a few hiccups. Here’s how to address them.

Artichoke Plants Not Producing Buds:

• Age: Some varieties need to be a year or two old before producing significant buds.
• Insufficient Sunlight: Ensure your plants are receiving adequate sun.
• Nutrient Imbalance: Too much nitrogen can lead to leafy growth without bud production.
• Stress: Extreme heat, drought, or inconsistent watering can inhibit flowering.

Yellowing Leaves:

• This can be a sign of overwatering, underwatering, or nutrient deficiency. Check your watering schedule and consider a soil test to assess nutrient levels.

Key Facts and Comparison

This table summarizes crucial information for growing globe artichokes from seed.

Pros and Cons of Growing from Seed vs. Buying Plants

Choosing the right starting method involves weighing the advantages and disadvantages.

Conclusion: A Rewarding Culinary Journey

Growing globe artichokes from seed is an endeavor that requires patience and attention to detail, but the reward of enjoying your own homegrown, tender artichoke hearts is immense. By following these comprehensive steps, from selecting the right varieties to providing meticulous care, you can successfully cultivate these magnificent plants and savor their unique flavor in your kitchen. Embrace the challenge, nurture your seedlings, and prepare to be delighted by the bounty of your artichoke patch. Happy gardening!