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 Shrubs Questions

Wound from non-native date palm thorn Naples FL
November 12, 2012 - Was trimming my pygmy date palm when a frond fell and a thorn pierced my rubber gloves and stuck me in the web of skin between my thumb and forefinger. Did not see a broken thorn but area where struc...
view the full question and answer

Native shrubs to plant after Ashe Juniper removal
February 15, 2010 - I live on 7 acres of beautiful Texas Hill Country land just north of New Braunfels. Live oak, Cedar elm, and Ashe juniper dominate the landscape. I have cleared some of the Ashe juniper and would li...
view the full question and answer

Source for non-native, invasive Winter Honeysuckle from Austin
April 24, 2013 - Seeing Lonicera abiflora today reminds me of the "winter honeysuckle" my grandfather grew in San Antonio from 1920s or so through the 1950's. It was a bush with stiff upright stems and bloomed cre...
view the full question and answer

Shrub that will grow outside in Zone 5 from Millbrook NY
April 21, 2012 - Is there any shrub, tree or other sort of plant that will grow well in zone 5 in a very large container outdoors?
view the full question and answer

Low growing native shrubs to go next to a rock pool deck
July 29, 2004 - I have a pool surrounded by a rock deck, & want to plant some low-growing shrubs next to the deck. However, I want to ensure the root system of the plant isn't invasive enough to crack the rock deck ...
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