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
Not Yet Rated

Monday - March 28, 2005

From: SF, CA
Region: California
Topic: Diseases and Disorders
Title: Pustules on geranium
Answered by: Joe Marcus

QUESTION:

I have a geranium that has developed oblong red/brown pustules/raised bumps on the undersides of the lower leaves. The foliage around the bumps is stil green but everything else has yellowed

ANSWER:

Thank you for writing! The problem you describe sounds like oedema (sometimes spelled: edema; pronounced: ed-ee'-ma). Oedema is not a disease, but a physiological disorder. It is a problem with many plants, but is an absolute disaster for geraniums (Pelargonium X hortorum) -- especially ivy geraniums (P. peltatum). Native geraniums are not as affected by the condition. Oedema is a result of ruptured cells, usually on the underside of a leaf, caused by a complex of issues involving water availability, humidity, temperature, air movement, and plant nutrient levels. In severe cases, the plant will drop the injured foliage, sometimes denuding the plant. The University of Georgia Cooperative Extension website has a nice article on Geranium Diseases including a section on oedema.
 

More Diseases and Disorders Questions

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

Trimming oaks and elms from New Braunfels TX
June 20, 2012 - I would like to trim my live oaks and elm trees at the same time, if possible. I think they are American Elms. When is the best time to do this and avoid oak wilt and Dutch elm disease? Should all c...
view the full question and answer

Juniper-apple rust galls
April 24, 2010 - I have Red Cedar trees in my yard. I have just noticed something that looks like a reddish brown squid-like bloom about the size of a small orange. Is this normal or is it a fungus?
view the full question and answer

Demise of Flameleaf Sumac in Austin, TX.
July 31, 2012 - My Flameleaf Sumac suddenly died. Beetles came out around the trunk when I cut it down. How can I prevent this on the other sumac?
view the full question and answer

Texas persimmon with scorched leaves from Austin
July 11, 2013 - I planted a Texas Persimmon seedling (five gallon) in my yard in early April. It is in a sunny, well-drained spot, and I have watered it regularly since planting. All was fine until the last weekend i...
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