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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


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


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




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