How to Grow Seed Potatoes: A Step-by-Step Guide for a Successful Harvest

Growing seed potatoes is an easy and rewarding way to enjoy fresh, homegrown potatoes. Seed potatoes are certified disease-free tubers that produce healthy plants and high yields. Whether you’re planting in a garden bed, container, or potato bag, learning how to grow seed potatoes correctly will ensure a productive harvest.

This guide covers everything you need to know about growing seed potatoes, from preparation and planting to care, harvesting, and storage.

What Are Seed Potatoes?

Seed potatoes are specially grown tubers certified as disease-free and used for planting. Unlike regular potatoes, seed potatoes are bred for reliable growth and high productivity.

Key Features

• Certified Disease-Free: Reduces the risk of diseases like blight and scab.
• Pre-Sprouted (Optional): Can be chitted to encourage early growth.
• Available in Varieties: Choose from early, maincrop, and salad types.

Types of Seed Potatoes

1. First Early Potatoes

• Planting Time: Late February to early March.
• Harvest Time: 10–12 weeks after planting.
• Examples: Rocket, Swift, Arran Pilot.
• Best For: Early harvests and new potatoes.

2. Second Early Potatoes

• Planting Time: Mid-to-late March.
• Harvest Time: 13–15 weeks after planting.
• Examples: Charlotte, Kestrel, Maris Peer.
• Best For: Salads and mid-season crops.

3. Maincrop Potatoes

• Planting Time: Late March to early April.
• Harvest Time: 18–20 weeks after planting.
• Examples: Maris Piper, King Edward, Desiree.
• Best For: Large harvests and long-term storage.

4. Salad Potatoes

• Planting Time: Mid-March.
• Harvest Time: 12–14 weeks after planting.
• Examples: Pink Fir Apple, Nicola, Ratte.
• Best For: Waxy potatoes for salads and light meals.

When to Plant Seed Potatoes

By Variety:

• First Earlies: Late February to early March.
• Second Earlies: Mid-to-late March.
• Maincrop: Late March to early April.

By Growing Conditions:

• Ensure the soil is workable and frost-free before planting.
• Use cloches or fleece to protect young plants in colder regions.

How to Grow Seed Potatoes: Step-by-Step

1. Prepare the Seed Potatoes

• Chitting (Optional but Recommended):
  • Start chitting 4–6 weeks before planting.
  • Place seed potatoes in a cool, bright spot with the eyes (sprouts) facing up.
  • Allow sprouts to grow to 2–3 cm before planting.

2. Prepare the Soil

• Choose a sunny location with well-drained, fertile soil.
• Add compost or well-rotted manure to improve soil fertility.
• Ensure the pH is between 5.5 and 6.5 for optimal growth.

3. Planting Seed Potatoes

In the Ground:

1. Dig trenches or holes about 10 cm deep.
2. Place seed potatoes with the sprouted eyes facing upward.
3. Cover with soil, leaving a slight mound to protect against frost.
4. Spacing:
   • First and second earlies: 30 cm apart with rows 60 cm apart.
   • Maincrop: 40 cm apart with rows 75 cm apart.

In Containers or Bags:

1. Fill the container or bag with 10 cm of soil or compost.
2. Place 3–5 seed potatoes evenly spaced on the surface.
3. Cover with another 10 cm of soil and water lightly.
4. Add more soil as the plants grow, leaving the top leaves exposed.

Caring for Growing Potatoes

1. Watering

• Keep the soil moist but not waterlogged, especially during dry spells.
• Consistent moisture is key during tuber development.

2. Earthing Up

• As plants grow, mound soil or compost around the stems to protect tubers from sunlight and prevent greening.

3. Fertilizing

• Apply a balanced fertilizer at planting and during early growth to encourage healthy plants.

4. Pest and Disease Management

• Pests: Protect plants from slugs, wireworms, and aphids using organic methods.
• Diseases: Use certified seed potatoes and rotate crops annually to prevent blight and scab.

5. Frost Protection

• Cover young plants with fleece or cloches if frost is forecast.

Harvesting Potatoes

1. First and Second Earlies

• Harvest when plants flower or the foliage begins to yellow, typically 10–15 weeks after planting.

2. Maincrop Potatoes

• Wait until the foliage dies back completely, around 18–20 weeks after planting.
• Use a garden fork to lift the tubers gently to avoid damage.

Storing Potatoes

1. Curing:
   • Dry harvested potatoes in a dark, cool, and dry place for 1–2 weeks.
2. Storage:
   • Store cured potatoes in a well-ventilated, dark location to prevent sprouting and greening.

Common Problems When Growing Seed Potatoes

1. Frost Damage

• Cause: Planting too early or exposure to late frost.
• Solution: Use cloches or fleece to protect young plants.

2. Blight

• Cause: Wet, humid conditions.
• Solution: Plant blight-resistant varieties and ensure good airflow around plants.

3. Green Potatoes

• Cause: Tubers exposed to sunlight.
• Solution: Regularly earth up soil to cover exposed tubers.

Tips for Growing Seed Potatoes Successfully

1. Start Early: Begin chitting in late winter to prepare seed potatoes for planting.
2. Rotate Crops: Avoid planting potatoes in the same spot each year to prevent soil-borne diseases.
3. Choose the Right Variety: Match your seed potatoes to your desired harvest time and culinary needs.
4. Monitor Moisture Levels: Keep soil consistently moist but avoid overwatering.
5. Protect from Frost: Cover young plants during frost warnings to prevent damage.

Top 10 Questions About Growing Seed Potatoes

1. What are seed potatoes?

Seed potatoes are small, certified disease-free tubers used for planting and growing potato crops.

2. When should I start chitting seed potatoes?

Start chitting 4–6 weeks before planting, typically in January or February.

3. How deep should I plant seed potatoes?

Plant seed potatoes about 10 cm deep.

4. Can I grow seed potatoes in containers?

Yes, seed potatoes grow well in containers or bags with proper soil depth.

5. How far apart should seed potatoes be spaced?

Space first and second earlies 30 cm apart and maincrop potatoes 40 cm apart.

6. How do I protect seed potatoes from frost?

Use fleece, cloches, or a layer of soil to protect young plants from frost.

7. How do I prevent potato blight?

Plant resistant varieties, ensure good airflow, and avoid overhead watering.

8. When should I harvest first early potatoes?

Harvest first earlies 10–12 weeks after planting when the plants flower.

9. How do I store harvested potatoes?

Cure potatoes in a dark, dry place for 1–2 weeks, then store them in a cool, ventilated area.

10. Can I grow potatoes from supermarket tubers?

It’s not recommended, as supermarket potatoes may carry diseases or have been treated to prevent sprouting.

Conclusion

Growing seed potatoes is a simple and rewarding process that provides a versatile and delicious crop. By preparing seed potatoes properly, planting at the right time, and following essential care tips, you can enjoy a successful potato harvest. Whether you’re growing in a garden, container, or potato bag, seed potatoes are a great addition to any gardening plan.