When to Plant Rhubarb: A Seasonal Guide for Success

Introduction

Rhubarb is a hardy perennial that’s easy to grow and can provide a bountiful harvest for many years. Whether you’re planting rhubarb crowns, seeds, or potted plants, timing plays a crucial role in ensuring healthy growth and high yields. Understanding the best time to plant rhubarb helps establish strong roots and sets the foundation for a productive plant.

This guide will explore when to plant rhubarb, the differences between planting crowns, seeds, and potted plants, and seasonal tips to maximize your rhubarb’s success.

Why Timing Matters for Planting Rhubarb

• Root Establishment: Planting at the right time allows roots to establish before the growing season.
• Weather Conditions: Rhubarb thrives in cool temperatures and benefits from planting during mild weather.
• Dormancy Periods: Dormant crowns are best planted during their natural rest phase for minimal stress.

Best Time to Plant Rhubarb

1. Bare-Root Crowns

• Ideal Time: Late autumn (October-November) or early spring (February-March).
• Why:
  • In autumn, the plant focuses on root growth as it prepares for dormancy.
  • In spring, the crown emerges from dormancy, and early planting helps it establish before active growth begins.

2. Potted Rhubarb Plants

• Ideal Time: Spring (March-May) or autumn (September-October).
• Why:
  • Potted plants can be transplanted more flexibly, but mild weather minimizes transplant shock.

3. Seeds

• Ideal Time: Indoors in late winter (January-February), outdoors in late spring (May).
• Why:
  • Indoor sowing ensures seedlings are ready to transplant after the last frost.
  • Direct outdoor sowing works well once the soil has warmed.

Planting Rhubarb by Season

1. Autumn Planting (October-November)

• Advantages:
  • The cooler temperatures encourage root development.
  • The plant will establish over winter and be ready to grow in spring.
• Tips:
  • Mulch heavily to protect the crown from frost.
  • Water sparingly to avoid waterlogged soil during wet weather.

2. Spring Planting (February-March)

• Advantages:
  • Early spring planting allows rhubarb to wake naturally from dormancy.
  • Ideal for bare-root crowns and potted plants.
• Tips:
  • Wait until the soil is workable and not frozen.
  • Water after planting to encourage root establishment.

3. Late Spring Planting (April-May)

• Advantages:
  • Suitable for potted plants and seeds as the soil has warmed.
  • The growing season provides time for the plant to establish.
• Tips:
  • Protect young plants from late frosts with fleece or cloches.

4. Summer Planting (June-August)

• Advantages:
  • Possible for potted plants, though not ideal.
  • Requires careful watering and shading in hot weather.
• Tips:
  • Avoid planting bare-root crowns, as they may dry out in the heat.
  • Mulch heavily to retain soil moisture.

5. Winter Planting (December-January)

• Advantages:
  • Suitable only in mild climates for dormant crowns.
  • Allows the plant to settle before spring growth.
• Tips:
  • Avoid planting during periods of frost or heavy rain.

How to Plant Rhubarb

1. Bare-Root Crowns

1. Choose a sunny or partially shaded spot with well-draining soil.
2. Dig a hole 12 inches wide and deep.
3. Add compost or well-rotted manure to the base of the hole.
4. Place the crown with buds facing upward, just above the soil surface.
5. Backfill with soil, firm gently, and water thoroughly.

2. Potted Rhubarb Plants

1. Remove the plant from its pot and loosen the roots.
2. Dig a hole twice the size of the root ball.
3. Place the plant with the crown at soil level.
4. Backfill with soil, firm lightly, and water well.

3. Seeds

1. Sow seeds indoors in seed trays filled with compost.
2. Plant seeds 1cm deep and keep the soil moist.
3. Place trays in a warm, bright location (18-21°C).
4. Transplant seedlings outdoors when they are 10-15cm tall and after the last frost.

Factors to Consider When Planting Rhubarb

1. Soil Preparation

• Test the soil’s pH and aim for a slightly acidic to neutral range (6.0-7.0).
• Enrich the soil with compost or well-rotted manure to improve fertility.

2. Drainage

• Rhubarb dislikes waterlogged soil, so ensure proper drainage.
• Consider raised beds if planting in heavy clay soil.

3. Spacing

• Allow 3-4 feet between plants to prevent overcrowding and promote airflow.

4. Mulching

• Apply a thick layer of organic mulch around the base of the plant to retain moisture and suppress weeds.

Common Planting Mistakes

1. Planting Too Deep

• Plant crowns with buds just above the soil surface to prevent rot.

2. Poor Soil Preparation

• Rhubarb needs nutrient-rich soil to thrive.
• Add organic matter before planting.

3. Waterlogging

• Avoid planting in poorly draining soil, as this can cause crown rot.

4. Planting in Full Shade

• Rhubarb tolerates partial shade but grows best in full sun.

FAQs About When to Plant Rhubarb

1. When is the best time to plant rhubarb crowns?

• Late autumn or early spring is ideal for planting bare-root crowns.

2. Can I plant rhubarb in summer?

• While not ideal, potted rhubarb can be planted in summer with careful watering and shading.

3. When should I plant rhubarb seeds?

• Sow seeds indoors in late winter or directly outdoors in late spring.

4. Can I plant rhubarb in winter?

• In mild climates, dormant crowns can be planted during winter if the ground isn’t frozen.

5. Is autumn or spring better for planting rhubarb?

• Both seasons work well, but autumn allows the crown to establish roots over winter.

6. How late can I plant rhubarb in the year?

• You can plant potted rhubarb as late as early autumn, but avoid planting too close to winter frosts.

7. What is the best soil for planting rhubarb?

• Rich, well-draining soil with plenty of organic matter and a pH of 6.0-7.0.

8. How do I prepare the soil for rhubarb?

• Add compost or well-rotted manure and ensure good drainage before planting.

9. How far apart should rhubarb plants be spaced?

• Space crowns or plants 3-4 feet apart to allow for growth.

10. Can I plant rhubarb under trees?

• Rhubarb tolerates partial shade but grows best in full sun with at least 6 hours of sunlight daily.

Conclusion

Knowing when to plant rhubarb is key to ensuring its long-term health and productivity. Whether you’re planting bare-root crowns, seeds, or potted plants, timing your planting for autumn or spring provides the best results. By preparing the soil, choosing the right location, and following proper planting techniques, you’ll enjoy bountiful rhubarb harvests for years to come.

Start planting your rhubarb at the right time and reap the rewards of homegrown, delicious stalks!