En EspaŅol

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
Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.
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

Control of Fusarium wilt on Wax Myrtle
March 05, 2011 - Do you have any new reports on how to control the Fusarium Wilt disease to Wax Myrtle Plants?
view the full question and answer

Why doesn't Diervilla lonicera bloom in Wisconsin?
June 11, 2015 - I have had a Diervilla lonicera in southeastern Wisconsin for at least 5 years. It has never bloomed. Why? It appears healthy.
view the full question and answer

Tulip trees losing bark in OH
July 11, 2011 - We have two tulip trees in our yard that are losing their bark at the base of the trunk. I am careful with the mower keeping away from the tree when I mow. What could the problem be and what can I d...
view the full question and answer

How to correct Anacacho leaves that are turning brown and curling in Driftwood, TX?
May 11, 2012 - Anacacho lunarioides leaves are turning brown and curling,how do I correct?
view the full question and answer

Problem with unknown tree in Austin, Texas
July 23, 2013 - Have recently moved to Austin, Texas and have a tree in my backyard that has been dropping leaves and one major branch appears to be dead. That branch has hard rust colored sap circles (about penny si...
view the full question and answer

Smarty Plants's Facebook profile Support the Wildflower Center by Donating Online or Becoming a Member today.

Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP | STAFF
© 2015 Lady Bird Johnson Wildflower Center