weed control in artemisia, Sweet Annie

Asked July 28, 2020, 11:14 AM EDT

I have a half acre of Sweet Annie planted. The weeds took over. I an aware that between the plants requires hand weeding. I can mow between the rows. But looking at a more long lasting control. What sprays can be use in the rows. I will protect the Sweet Annie since it looks like hand spraying is the way to proceed. Plants are between 3 and 4 feet tall.

Kent County Michigan

1 Response

Hello,

Artemisia annua, Sweet Annie, is an annual and so you can use annual flower bed controls or field crop controls. You have been referred to the gardening section of Ask an Expert so, I will give you garden bed controls. If you want advice for field crops, let me know and I will find an Agricultural section expert to assist you.

You are correct, if you want to use chemicals you need to hand paint on weedkiller or shield the artemisia with cardboard while spraying.

Use weed killer meant for the control of the weeds you have. For example, pigweed: http://www.msuturfweeds.net/details/_/redroot_pigweed_32/

Another example, lambsquarters: http://www.msuturfweeds.net/details/_/common_lambsquarters_31/

The above website has many common weeds found in turf and garden and their control and management options. If prompted to”login” enter a email id as a login ID with your zipcode as a password.

You can use 20% acetic acid herbicide applied according to label precautions and directions- burns tops down, and must be repeated to starve perennial weed roots. http://ucnfanews.ucanr.edu/Articles/Feature_Stories/Organic_Herbicdes_-_Do_They_Work/

You can use a nonselective control like glyphosate. Glyphosate does not move through the soil. So, painting it on a weed won’t ‘ transmit’ to the nearby artemisia. Shield all desirable plants from any spray or drips and apply only according to the label windspeed and air temperature parameters.

Please follow all label precautions and directions of any product; even organic ones are strong enough to irritate skin, lungs, or eyes.

For next season, mulch 3 inches deep around the plants will discourage future weeds from germinating. Hoeing to cut weeds at or just below soil level controls weeds. Placing a pre-emergent weed control after your artemisia has germinated and has grown several inches can control later emergence of weeds from seed.

References-

https://ucanr.edu/datastoreFiles/268-549.pdf

www.msuturfweeds.net

https://planttalk.colostate.edu/topics/weeds-cultural-problems/2118-herbicides-pre-emergent/

If you have a specific weed you are trying to control and didn’t find it at the above MSU link, please reply here and I will try to find information for you.