Rent Shop Volunteer Join

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

Friday - December 03, 2010

From: Georgetown, TX
Region: Southwest
Topic: Compost and Mulch, Diseases and Disorders, Pests, Vines
Title: Fungus Spots on Native Bush Honeysuckle
Answered by: Brigid & Larry Larson

QUESTION:

My native bush honeysuckle plants that I have along my back fence have leaves that are turning yellow with spots. It appears to be a type of fungus, but not powdery mildew. Any suggestions as to what I can do?

ANSWER:

First of all, without seeing your plant, there are lots of possible causes of yellowing and spots, so Mr. Smarty Plants’ diagnosis of the cause is likely to be only slightly more valuable than what you paid for it.    To be sure of what is afflicting your vine you should contact your state's Cooperative Extension Service for an accurate diagnosis.

In searching for the issue of leaf-spots on Honeysuckles, the book “Diseases and pests of ornamental plants” by Pascal Pompey Pirone noted that “Five fungi are known to cause leaf spots of bush-honeysuckle” and goes on to list them.  Several other references also mentioned that the Bush Honeysuckle is subject to fungal diseases such as leaf blight, canker and powdery mildew.  So your suspicion that it appears to be a type of fungus is likely to be accurate.  The only other real possibility for the leaf spots is that it might be the effect of Spider mites.   Gardenguides.com notes that “Aphids and spider mites are common insect pests of the honeysuckle species plants. The honeysuckle aphid causes leaves to curl and turn yellow, while the spider mite makes the leaves appear stippled with red or yellow spots” 

With winter quickly approaching, one very natural thing you can do is clean up the yard.  Trim off all the affected vines and make sure all the leaves and other debris are picked up and discarded in the garbage.  This is one time we won’t recommend that you compost the garden debris!  Honeysuckles are OK with pruning; in fact a possible fungal infection will be decreased by opening up the plant, which can be quite dense, to light and good air circulation.

Yardener.com has some good advice for control with natural fungicides. They suggest using baking soda, Neem extracts and/or control with sulphur.  They also have a very appropriate section on Control without fungicides that looks a lot like my “cleanup” advice above.

That’s a reasonable set of suggestions for fungi, but what about spider mites?  Once again, cleaning up is one of the better first steps.  If they are still there in the Spring – then maybe insecticidal soap spray is an effective natural control for insects including both the spider mite and the honeysuckle aphid.

Diervilla sessilifolia (Southern bush honeysuckle)    Diervilla lonicera (Northern bush honeysuckle)

                                     

 

More Diseases and Disorders Questions

Fungal root rot in non-native Shasta daisies in Channahon IL
July 21, 2009 - HELP! My Shasta daisies have fungal root rot. Is there any way to save them? I've been removing the browned stems. I'm so sad.
view the full question and answer

Problems with October Glory maple tree in Evansville IN
June 10, 2010 - We have a 15 yr. old October Glory maple tree. 2 years ago we had a bad ice storm and this tree was covered with 1/2 to 3/4 " of ice. The tree resembled a chicken wishbone with its limbs touching ...
view the full question and answer

Problems with non-native Cleyera and Red-tip photinia
June 01, 2008 - I planted a row of Cleyera in a bed that receives sunlight for about 3 hours during the middle of the day. My problem is that a number of the plants are dying. It begins with the leaves on one small...
view the full question and answer

Moth using Agarita as its larval food in New Braunfels, TX
March 27, 2009 - What moth uses agarita as its larval food? It is a perennial problem that can nearly defoliate the specimen and severely limit its flower production.
view the full question and answer

Dying trees in San Marcos, Texas
September 24, 2011 - I live on 11 acres in San Marcos and cannot water at all during this drought. All of my oaks and mountain laurels are turning brown. Does this mean they are all dying? Will they come back in the sp...
view the full question and answer

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