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

Wednesday - November 13, 2013

From: Rockville, MD
Region: Mid-Atlantic
Topic: Diseases and Disorders, Seasonal Tasks, Wildflowers
Title: Cutting Back Perennials in the Fall?
Answered by: Anne Van Nest

QUESTION:

We have large beds of flowering native perennials that we planted around our house as part of a landscape conservation plan (various Joe-Pyes, goldenrods, turtlehead, blazing star, brown-eyed Susans). Fall is upon us in Montgomery County, MD, and we see lots of birds having a great time kicking around in the leaves from the trees that are littering the beds. In the past we've cleaned the beds out down to the mulch layer before winter, but I'm starting to wonder if this is best for the plants and animals. Do we have to clean out the tree leaves before winter to keep the plants healthy? Can we leave them, or will this promote too much disease?

ANSWER:

The only parts of the garden that really need to be cleaned up well (down to the mulch or even replace this too) are any area around a seriously diseased plant. While native plants are generally disease and pest free, some problems like powdery mildew on phlox, leaf spot on bugbane, or overwintering leafminer on gaillardia could be serious enough to harm the plants. In this case all the affected foliage should be removed so that the fungus spores or insect eggs and pupa do not overwinter.  For the rest of the garden, healthy woody perennials can often be left intact or pruned to 6 inches for the winter.  Any seeds or insects still on the plant will be welcome food for the wildlife and the uncut stems will help collect insulating snow around the plant and give it extra protection as well as mark where the plants are located next spring.
Any fleshy perennials though (like touch-me-nots) should be removed in the fall since they will turn into a mushy mess after the first frost.
Leonard Perry of The University of Vermont Extension has posted a good information sheet on Fall Perennial Care online.

 

From the Image Gallery


Joe-pye weed
Eupatoriadelphus maculatus

Ohio goldenrod
Oligoneuron ohioense

Pink turtlehead
Chelone lyonii

Ontario blazing star
Liatris cylindracea

Black-eyed susan
Rudbeckia hirta

Fall phlox
Phlox paniculata

Firewheel
Gaillardia pulchella

Jewelweed
Impatiens capensis

More Seasonal Tasks Questions

Freeze damage to esperanza in pot from Brady TX
December 10, 2009 - My esperanza, currently in a container, has suffered some freeze damage. I have prepared a planting spot for it and am not sure whether to plant now, trim it back if I do plant it, etc. I would appr...
view the full question and answer

Drought affecting native trees from The Woodlands
August 18, 2011 - I've been trying to grow native trees in my yard for the past 3 years and I'm starting to question whether the amount of time required to spend watering them during the long hot season in Texas is r...
view the full question and answer

Overwintering Texas bluebonnets
November 17, 2011 - I planted Texas Bluebonnet and I want to know how to save them through the winter months. I think they are so beautiful. Can I cover them with something?
view the full question and answer

Trimming native salvias in January
January 17, 2008 - I have heard you can trim Hot Lips, Raspberry and other salvias back severely in January, to about six inches from the ground. Is this correct?
view the full question and answer

Damage to plants after sudden freeze in Redway CA
January 02, 2010 - I live on the North Coast of California near "The Avenue of the Giants" and Redwoods State Park along the Eel River. We recently have had below freezing weather, constant rain and even snow! I have...
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
© 2014 Lady Bird Johnson Wildflower Center