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Purpletop vervain · Verbena bonariensis

Why is my Purpletop vervain not flowering?

Purpletop vervain is famous for its long blooming season, so a lack of flowers is frustrating. The most common cause is a lack of direct sun. Start by checking if your plant is getting enough light.

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Check these first

  1. Verify the plant gets at least 6 hours of direct sun.
  2. Check the soil for signs of heavy nitrogen buildup.
  3. Look for any pests that might be eating the flower buds.

Likely causes

  1. Lack of Direct Sun

    Most likely

    How to tell: The plant looks healthy and green but produces no flower buds.

    What to do: Ensure the plant receives full sun for most of the day. If it is shaded by other plants, prune back the neighbors to let the light in.

  2. Improper Fertilizer

    Possible

    How to tell: The plant is growing very fast but shows no signs of budding.

    What to do: Avoid high nitrogen fertilizers which favor leaves over flowers. Use a bloom boosting fertilizer with higher phosphorus content if necessary.

Other plants that won't flower

Find out what's wrong with your purpletop vervain

The list above covers the usual causes. Pocket Botanist looks at a photo of your actual plant and tells you the likely cause, how serious it is, and what to try first. Identification and a health check are free.

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When to worry

If it is still early in the season, give it time as they often start blooming in mid summer. If it is late summer and there are no buds, you have a problem.

Stopping it coming back

Keep the plant in full sun and avoid over fertilizing.

Purpletop vervain: not flowering? Check yours with a photo

Every plant is a little different. Take a photo of your purpletop vervain and Pocket Botanist tells you which cause is most likely, how serious it is, and what to try first. A few checks a day are free. Save the plant and you get care reminders timed for it.

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Questions people ask

Does deadheading help?
Yes, removing spent flower heads can encourage the plant to produce more blooms throughout the season.
Can overwatering stop flowering?
Yes, soggy soil can stress the plant and prevent it from putting energy into flowers. Let the soil dry out between waterings.

More problems with Purpletop vervain

Back to the Purpletop vervain guide

This article was generated with AI on from the plant’s care profile and is general information, not horticultural advice. Read about how we build these guides.