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

Tuesday - June 18, 2013

From: Magnolia, TX
Region: Southwest
Topic: Pruning, Shrubs
Title: Pruning Ageratina havenensis from Magnolia TX
Answered by: Barbara Medford

QUESTION:

I planted a Eupatorium havanense last year here in the last sandy finger of the piney woods; it gets full sun in a well-drained raised bed, where it flowered well. I pruned it fairly close, and it came through the mild winter without any extra watering. It has been putting out blooms, one or two branches at a time, since late February. Should I be pruning back the branches that have bloomed so as to guarantee enough new growth for it to bloom all over in the autumn, or should I be glad it bloomed at all?

ANSWER:

This plant appears in our Native Plant Database as Ageratina havanensis (Havana snakeroot); Eupatorium havanensis is an older name, now considered a synonym.  As you can see from this USDA Plant Profile Map, it grows somewhat west of Montgomery County, and we are not sure the soils would be similar. However, if you are growing it, it must be okay there.

From our webpage on this plant:

"White mistflower provides late summer and early fall color. Blooms best and appears bushier if severely cut back each winter."

That keeps you from deciding whether to cut back the present blooms in hopes of more blooms later. It should continue to provide color until early Fall and then can be pruned back hard in November to January. Perhaps the extra blooming is the result of more rain and lusher soils in your part of the state.

 

From the Image Gallery


Shrubby boneset
Ageratina havanensis

Shrubby boneset
Ageratina havanensis

Shrubby boneset
Ageratina havanensis

More Pruning Questions

Questions about care and pruning of Mexican Plum and Mountain Laurel in Austin, TX.
January 24, 2012 - I have a couple of questions regarding tree care and pruning. I have a Mexican Plum (Prunus mexicana), about 10 years old or so. I would like to prune it. Is it ok to prune now in late wi...
view the full question and answer

Pruning Bald Cypress in Wylie, TX
January 02, 2010 - I have a 6 year old bald cypress that sustained damage to the upper portion of its trunk a couple of years ago. Since that time it has grown more outward than upward and developed a rounder shape. I...
view the full question and answer

Pruning Post Oaks
July 26, 2014 - I live in Houston and have two post oaks. One is right by my house. I'd like to trim them but was told they are sensitive and might die if I trim them. Is this true? What is the right course of ac...
view the full question and answer

Smarty Plants on mockoranges
May 25, 2005 - I live in Colorado where it is common to have 1 or 2 late frosts. I planted 4 littleleaf mockoranges (Philadelphus Microphyllus) 2 years ago and they are pretty much in full sun most of the day. I h...
view the full question and answer

Perennial summer blooming plant for Livonia, MI
May 22, 2009 - I want to find a plant that I can cut back in the fall, will come back in the spring, flower throughout the summer, be a medium size plant, no taller than 48", about 36" in diameter. It would get f...
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