En Español

Q. Who is Mr. Smarty Plants?

A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?

Share

Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
    
 
See a list of all Smarty Plants questions

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

 
rate this answer
1 rating

Sunday - July 20, 2008

From: Houston, TX
Region: Southwest
Topic: Container Gardens
Title: Failure of potted verbena to bloom
Answered by: Barbara Medford

QUESTION:

I have a trailing purple verbena that won't bloom. It is in a container, not in the ground, and gets lots of sun. What is the problem?

ANSWER:

In our Native Plant Database, there are 36 species with the name "verbena" in the name of the plant, most members of the genus Glandularia. Probably the most-used native verbena is Glandularia bipinnatifida (Dakota mock vervain). We are pretty sure that what you have is some sort of a hybrid, with different colors, as that is what is usually available in commercial nurseries. Since we don't know, and you were probably not given any indication, what hybrid this would be, we can only deal with your question on a general basis. This website from GardenGuides.com Verbena can give you some more care information, regardless of the species. In cooler climates, verbena are considered annuals, but in Houston, you should be able to get it to perennialize. You said it was in a container, so you need to make sure the container drains very well. The verbena needs moist soil until it is pretty well-established, but cannot tolerate soil that does not drain well, and may develop disease because of the poor drainage. The native verbena mentioned above blooms from March to October. Although our webpage on the verbena says it needs part shade, which we define as 2-6 hours of sun a day, other websites say that verbena needs full sun, up to 8 to 10 hours a day of sun. A plant that needs lots of sun to bloom is not going to do well in a more shaded location. If blooms seem to slow during the summer, you might trim the whole plant back by about 1/4, and hopefully it will recover its vigor and bloom again. Dedheading is important on this plant but, again, just trimming across the top to take off spent blooms should suffice, instead of snipping off each individual blossom. If your plant has lush foliage and no flowers, we suspect the plant food you are giving it is heavy on nitrogen, which promotes green leaves. Switch to one that has a higher phosphorus content, the number in the middle of fertilizer designations, and see if that will inspire your plant to bloom.

 

From the Image Gallery


Prairie verbena
Glandularia bipinnatifida

More Container Gardens Questions

Potted Plumbago, struggling with the heat, in Spring Texas
June 29, 2011 - Why do some of the leaves of my plumbagos that are grown in large, well-draining planters turn brown? The brown starts on the tips, then extends to the whole leaf. They get several hours of west aft...
view the full question and answer

Hanging Baskets for Batson, TX
May 23, 2014 - What plants can I put in hanging baskets for my shady porch?
view the full question and answer

Growing bluebonnets in pot in Flower Mound TX
November 01, 2011 - We received a package of bluebonnet seeds along with the DVD Wildflowers: Seeds of History as a gift. In the film, Andrea DeLong mentions that bluebonnets did not grow well in a rich organic soil. W...
view the full question and answer

Care for indoor Lemon Cypress
November 30, 2008 - How do I care for an indoor Lemon Cypress tree?
view the full question and answer

Planter boxes on a roof deck in Boston MA
May 20, 2013 - What will grow in planter boxes on a roof deck in Boston ma? We are planning to make our own planters to sit on the framing "outside" our deck rail. We have 4 ft from the rail to the edge of the ho...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | JOBS | SITEMAP | STAFF INTRANET
© 2016 Lady Bird Johnson Wildflower Center