Rhubarb Flower: What It Means and What to Do

Introduction

If you’ve noticed a tall stalk with a cluster of flowers growing from your rhubarb plant, don’t worry—you’re not alone. Rhubarb flowering, also known as bolting, is a natural process that can occur under certain conditions. While the flowers may look striking, they can affect the growth and productivity of your plant.

In this guide, we’ll explain why rhubarb flowers, what it means for your plant, and how to manage and prevent bolting to ensure a healthy and productive rhubarb patch.

Why Does Rhubarb Flower?

Flowering in rhubarb occurs when the plant produces a tall stalk topped with a cluster of flowers. This process, known as bolting, is the plant’s way of reproducing by setting seeds. While bolting is natural, it can reduce the plant’s energy for producing edible stalks.

Common Causes of Flowering

1. Plant Age

• Older rhubarb plants are more likely to flower as they reach the end of their productive lifespan.

2. Stress

• Stress caused by drought, overcrowding, or poor nutrition can trigger flowering.

3. Variety

• Some rhubarb varieties, such as ‘Victoria,’ are more prone to flowering than others.

4. Temperature Fluctuations

• Extreme heat or sudden temperature changes can cause bolting.

5. Daylight Length

• Longer days in late spring and early summer can encourage flowering.

Is Rhubarb Flowering Bad?

While rhubarb flowers are not harmful to the plant, they can divert energy away from producing stalks, leading to smaller, thinner, or fewer stalks. This reduces the overall harvest and can weaken the plant over time.

What to Do When Rhubarb Flowers

If your rhubarb starts to flower, follow these steps to manage the situation:

1. Remove the Flower Stalk

• Cut the flower stalk as soon as you notice it. Use sharp pruners or a knife to cut it as close to the base as possible.

2. Water Consistently

• Keep the soil consistently moist to reduce stress and prevent further bolting.

3. Feed the Plant

• Apply a balanced fertilizer or compost to replenish nutrients and boost the plant’s energy.

4. Check for Crowding

• If the plant is overcrowded, consider dividing it in early spring or late autumn to give it more space.

5. Mulch Around the Base

• Mulch with organic matter to retain moisture and regulate soil temperature.

How to Prevent Rhubarb Flowering

1. Water Regularly

• Water rhubarb consistently, especially during dry spells, to prevent drought stress.

2. Feed Annually

• Apply a nitrogen-rich fertilizer in early spring to encourage strong foliage and stalk growth.

3. Divide Older Plants

• Divide rhubarb crowns every 5-7 years to maintain plant vigor and reduce the risk of bolting.

4. Choose Bolt-Resistant Varieties

• Some varieties, like ‘Timperley Early’ and ‘Glaskins Perpetual,’ are less prone to bolting.

5. Provide Shade During Heatwaves

• Protect rhubarb from extreme heat by providing shade with cloth or screens.

Are Rhubarb Flowers Edible?

No, rhubarb flowers are not edible and should not be consumed. The flowers and leaves contain high levels of oxalic acid and other compounds that are toxic to humans and pets. Only the stalks are safe to eat.

Can You Harvest Rhubarb After It Flowers?

Yes, you can still harvest rhubarb after it flowers, but the stalks may be smaller or less flavorful. Removing the flower stalk promptly helps redirect the plant’s energy into producing better stalks. Avoid harvesting more than one-third of the plant’s stalks at a time to avoid stressing it further.

FAQs About Rhubarb Flowers

1. Why is my rhubarb flowering?

• Rhubarb flowers due to age, stress, temperature fluctuations, or genetic predisposition.

2. Should I cut off rhubarb flowers?

• Yes, remove flower stalks as soon as they appear to redirect energy into stalk growth.

3. Can I eat rhubarb flowers?

• No, rhubarb flowers are not edible and contain toxic compounds.

4. How do I prevent my rhubarb from bolting?

• Water consistently, feed annually, and divide older plants to reduce stress.

5. Does flowering mean my rhubarb plant is dying?

• Not necessarily, but flowering can indicate age or stress. Dividing or rejuvenating the plant can help.

6. How often should I water rhubarb to prevent flowering?

• Water deeply once a week during dry periods, ensuring the soil stays moist but not waterlogged.

7. Can rhubarb flower every year?

• Yes, some plants may flower annually, especially older or stressed plants. Removing flower stalks helps maintain productivity.

8. What is the best fertilizer to prevent rhubarb flowering?

• Use a nitrogen-rich fertilizer in early spring to encourage strong foliage and stalk growth.

9. When is the best time to divide rhubarb?

• Divide rhubarb in early spring or late autumn when the plant is dormant.

10. Will my rhubarb recover after flowering?

• Yes, with proper care, rhubarb can recover and continue producing stalks.

Fun Facts About Rhubarb Flowers

1. Dramatic Appearance: Rhubarb flower stalks can grow up to 5 feet tall, making them a striking sight in the garden.
2. Seed Production: If left to flower, rhubarb produces seeds that can be used to grow new plants.
3. Natural Evolution: Flowering is the plant’s natural way of reproducing and spreading its genetics.

Conclusion

While rhubarb flowering can be surprising, it’s a natural part of the plant’s lifecycle. By understanding why rhubarb bolts and how to manage or prevent it, you can maintain healthy plants and enjoy bountiful harvests. Remove flower stalks promptly, reduce plant stress, and follow best practices to keep your rhubarb thriving for years to come.

Keep your rhubarb patch productive and enjoy the satisfaction of fresh, homegrown stalks!