MAY
2012

 

 

 

By
B. Rosie Lerner
 
Purdue
Extension
Consumer Horticulturist

 

Check out Rosie's book:Possum in the Pawpaw Tree

 

 

 

05-03-12

Question and Answer


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Q. What is the best way to eradicate henbit? Would a weed-and-feed in fall or spring be most effective? Would a spray weed killer be most effective in spring or fall? Could you use a pre-emergence like crabgrass preventer in the fall?

A. Henbit is a winter annual, meaning it germinates from seed in the fall, overwinters in a dormant state and then blooms and sets seed to complete its lifecycle in late winter/early spring. By mid- to late spring, the foliage will turn yellow, but if allowed to remain until then, it will have produced a lot of seed to germinate in years to come. 

Prevention is really the key to henbit control.  In the garden or landscape, hand removing, hoeing, tilling and other mechanical methods are effective if done early enough to prevent seed formation. A healthy, vigorous lawn will out-compete henbit.

Chemical controls might be helpful if you are so inclined, but choice of specific product depends on the specific site; lawn vs. ornamental flower/shrub bed vs. vegetable or fruit garden. A pre-emergence herbicide applied in late summer/early fall can help reduce the number of plants that will emerge next year. Broadleaf weed killers can be applied after the plants emerge either in fall while the henbit is still actively growing or in early spring before plants flower. However, the active ingredients effective in controlling henbit post-emergence are also highly likely to injure your desirable plants in the garden and landscape.

Henbit is frequently confused with two other weeds: purple deadnettle and ground ivy.  All three are in the mint family and have square stems with opposite leaves and blue-purple flowers. You'll find information and photos to help distinguish these three garden thugs at www.ppdl.purdue.edu/ppdl/weeklypics/Weekly_Picture4-15-02-1.html.

Japanese flowering cherry
Prunus serrulata

Q. My daughter lives in extreme northern Steuben County, a few hundred yards from the Michigan state line. Recently while driving to work, she saw this plant, liked it, took this picture and sent it to me (Dad) to identify. Not my thing. While it looks familiar, I can't put a name to it. Can you please help?

A. That looks to be a Japanese flowering cherry (Prunus serrulata), which is available in either single- or double-flowered form as well as white or pink. The flowers are really showy when they do perform, but in our area many years the flower buds are winter-killed. The mild winter and earliness of this year's spring no doubt was one of the finest displays you will ever encounter for this plant.

 

Writer: B. Rosie Lerner
Editor: Olivia Maddox,