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
2 ratings

Sunday - May 18, 2008

From: Kerrville, TX
Region: Southwest
Topic: Compost and Mulch, Diseases and Disorders, Planting, Herbs/Forbs
Title: Chlorosis in tropical milkweed and asclepias tuberosa
Answered by: Barbara Medford

QUESTION:

I planted both tropical milkweed and asclepias tuberosa. Both are chlorotic and the native milkweed has brown upturned leaves. Could it possibly be too much water? Or what?

ANSWER:

Asclepias curassavica, or Tropical Milkweed, is a native of South America and therefore does not appear in our Native Plant Database. However, here is a Floridata website on it for reference. Asclepias tuberosa (butterfly milkweed) is a native and you can click on the link and read the information on it in our database.

Chlorosis is a yellowing of leaf tissue due to a lack of chlorophyll. Possible causes of chlorosis include poor drainage, damaged roots, compacted roots, high alkalinity, and nutrient deficiencies in the plant. Nutrient deficiencies may occur because there is an insufficient amount in the soil or because the nutrients are unavailable due to a high pH (alkaline soil). Or the nutrients may not be absorbed due to injured roots or poor root growth.

The Asclepias genus usually does not require a great deal of water, but if the soil is not draining well, the roots will be inhibited from picking up the trace elements in the soil, especially iron, and that will result in the plants becoming chlorotic. The major cause of chlorosis is a deficiency of one of the essential micronutrients such as iron or manganese. This deficiency occurs not because the nutrients are lacking in the soil but because they are unavailable due to a high-pH soil. At these higher soil pH levels (6.5 and above) many trees and shrubs are incapable of taking up adequate amounts of iron or manganese. This part of Central Texas has a lot of alkaline soil; however, some compost mixed into the soil or used as a top dressing often will address the problem, providing better drainage, reducing the alkalinity and improving the texture of the soil and permitting access to the trace elements needed.

 

More Diseases and Disorders Questions

Pecan tree dropping limbs in Grand Prairie, TX.
September 04, 2012 - Our 15 year old pecan tree is losing it's limbs. The tree and its leaves look healthy with no signs of bugs or mites, but all the limbs are drooping and breaking off. The tree did have a bumper crop ...
view the full question and answer

Reason for tree canopy dieback from Mahopac NY
May 21, 2012 - Dear Mr. Smarty Plants: Not a questions, just sharing, re person in Texas whose Ash Jupiter appeared to be dying "canopy very thin on top". We moved to Putnam Co. NY in 1970. Our house was shaded by...
view the full question and answer

Are brown junipers (Juniperus ashei) dead?
November 08, 2011 - If the cedar/junipers in our area are brown, will they ever come back green? Or just clear them out as dead. There are many of them due to the drought. Thank you.
view the full question and answer

Smarty Plants on lantana in Dallas
September 14, 2005 - For several years, the lantana plants in my backyard in Dallas grew and bloomed all Summer and Fall until the first real cold snap. I've loved having a native plant that didn't need constant care a...
view the full question and answer

Petals not developing on blackeyed susans from Nashville TN
July 05, 2011 - 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...
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