Host an Event Volunteer Join Tickets

Support the plant database you love!

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
1 rating

Monday - July 06, 2009

From: Lake Ronkonkoma, NY
Region: Northeast
Topic: Compost and Mulch, Propagation, Transplants, Herbs/Forbs
Title: Dividing blackeyed susans in Lake Ronkoko NY
Answered by: Barbara Medford

QUESTION:

How are you supposed to divide blackeyed susan's? And when is the best time to do this?

ANSWER:

The only plant we found with the common name "Blackeyed Susan" native to New York is Rudbeckia hirta var. pulcherrima (blackeyed Susan). According to the information in our Native Plant Database, this is a biennial, which may perennialize if it's happy where it is. So, we're going to go on the assumption that your plants are happy, and suggest you divide them in early fall in your climate, preferably after the first cool nights, but when the soil is still warm. The plant will be going into dormancy then and won't be quite so subject to transplant shock. You can spend some time between now and then preparing their new home, possibly adding some compost and working it in to improve drainage and to help make trace nutrients in the soil more available to new roots. 

We found an excellent website by Fine Gardening, 10 Tips on Dividing Perennials, which gives you information in a much more organized form than we could. 


Rudbeckia hirta var. pulcherrima

Rudbeckia hirta var. pulcherrima

Rudbeckia hirta var. pulcherrima

Rudbeckia hirta var. pulcherrima

 

 

 

More Herbs/Forbs Questions

Removal of previously-planted perennials
July 23, 2008 - HI I JUST MOVED INTO A NEW HOUSE THIS YEAR THE PREVIOUS OWNERS PLANTED A LOT OF BEAUTIFUL PERENNIALS BUT I WANTED TO PLANT OVER ONE OF THE PERENNIALS THAT I REALLY DO NOT CARE FOR. IS THAT POSSIBLE? I...
view the full question and answer

What is the black stuff growing on my thoroughwort?
October 27, 2015 - What is the black stuff on my thoroughwort plant's leaves that is killing the plant?
view the full question and answer

Gregg's Mistflower stressed in Fredericksburg TX
August 07, 2013 - My Gregg's Mist Flower plants are very stressed. The blooms have turned brown and the leaves are drooping. Plants are receiving moderate sun, partial shade. Do they need daily watering this time o...
view the full question and answer

Evergreen for sunny, dry area under a maple in Connecticut
October 10, 2015 - I have a sloped, very sunny, dry area under a maple. I was wondering if Sweet Fern would be a likely candidate for this area. I would like it to be evergreen and to be able to survive under mounds of...
view the full question and answer

Shade tolerant groundcover plants for Tarrant County, Texas
November 01, 2011 - I live in far NE Tarrant County (Ft Worth), TX and need a groundcover that can tolerate complete shade and poor, rocky, clay soil. I need mostly for erosion control, and needs to be relatively low
view the full question and answer

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