Host an Event Volunteer Join Tickets

Support the plant database you love!

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
4 ratings

Tuesday - July 05, 2011

From: Nashville, TN
Region: Southeast
Topic: Diseases and Disorders, Pests, Herbs/Forbs, Wildflowers
Title: Petals not developing on blackeyed susans from Nashville TN
Answered by: Barbara Medford

QUESTION:

I have an established "patch" of black eyes susans. This year, the leaves are beautiful, the centers black..but the petals are practically non existent. They didn't seem to develop correctly. Any idea what's up?

ANSWER:

Rudbeckia hirta var. pulcherrima (Blackeyed susan) appears on this USDA Plant Profile map to be native in or near Davidson Co., and you say your patch is established, so the soils should not be the problem. This plant is pollinated by bees and flies but also attracts butterflies, and is a larval host for the Silvery Checkerspot.

Do the petals look like they have been chewed at all, or are they stunted or misshapen? Take a look at this page of images of Blackeyed Susan from our Native Plant Image Gallery. There seems to be quite a variety of leaf types and colorations, but no closeups, at least, of flowers with stunted petals. If you find any caterpillars, they could be the culprit, and are probably the larvae of the butterfly mentioned above.

If you have eliminated all those problems from consideration, we can only fall back on the weather. Here in Texas, we are in such an extreme heat wave and drought that flowers bloom, set seed and go into near dormancy, just to survive. The Blackeyed Susan is a biennial or can be a short-lived perennial. This plant does not need to be fertilized, but it does like some moisture. Our best bet is that it is adapting itself to adverse conditions, but continuing to set seed (the black center), and hold on until the weather gets a little easier on plants and people.

 

More Diseases and Disorders Questions

Problems with dogwood tree in Jacksonville FL
February 28, 2010 - Sir, I believe I have a Cornus drummondii, a stiff dogwood tree on my lawn which a few years ago was big, lush and full of branches and leaves. In the last 2 years I have noticed about 80% of it drop...
view the full question and answer

Transplant shock in Dakota mock vervain
July 23, 2007 - We just planted some Verbena bipinnatifida in our back yard and when we planted it, it had purple flowers on it but now they've all dried up. We live in central Colorado and thought this plant was fa...
view the full question and answer

Is post oak resistant to oak wilt from Dallas TX
November 22, 2013 - I am confused. The NPIN website says that Post Oak IS susceptible to oak wilt, but all the other information I have been able to find says that it is resistant to oak wilt and rarely gets the diesase....
view the full question and answer

Mountain Laurel having trouble in AZ
June 07, 2011 - A Sophora secundflora (Texas mountain laurel) was planted to an Arizona north faced front yard last year in August under full sun. Starting early this year, I noticed its leaves turn to light green an...
view the full question and answer

Shade Loving Plants for Under a Black Walnut Tree in Rochester, NY.
May 09, 2015 - Please advise on plants that will grow in the shade under a black walnut tree in Rochester, NY.
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.