Milkweed - position

Asked May 22, 2019, 11:51 AM EDT

Hi, I was just at the Schwartzs Greenhouse in Romulus MI and asked if they had any common milkweed. I was told by a staff member (quite emphatically) that they do not carry it because “milkweed is an invasive!” When I questioned this and asked for further info, she told me that MSU has a position stating that it is an invasive, and that you, their greenhouse and others are "working with farmers to eradicate this invasive plant."

Before I take any further steps to follow up with them about this, I thought I should reach out directly to you to be sure I am not missing anything. The only new information that I have seen put out by you is about the benefits of mowing, and details of the monarch predation study from May 2019. Thanks in advance so much for your wisdom and advice.

Washtenaw County Michigan

5 Responses

Hi. First of all there might be a problem with terminology. ‘Invasive’ usually means something that is hurting our native environment, whether insects or plants. Other plants that spread easily can be called ‘agressive’. If you google ‘MSU milkweeds’ all kinds of info pops up about it, mostly positive. Perhaps it is a problem in crop fields (that is out of my knowledge area) but I have never heard it called invasive. Please let me know if you have further questions after looking on google. Thank you.

Thank you for your reply. I had already done quite a bit of googling "MSU Milkweed" before reaching out to you, and referenced what I saw as the most recent piece from May 2019 describing a monarch predation study. Everything that I have seen has been positive, but before I approach the Schwartz Greenhouse management, I was hoping to get a definitive answer on whether or not Michigan State has in fact come out with anything stating that people should not plant milkweed. To be clear, she stated that they do not carry it because MSU has broadly proclaimed that it should be eradicated. Given that this is a pivotal plant - and issue, I wanted to be very clear in my understanding that this is definitively NOT MSU's position. Is there someone I could reach out to, perhaps, if you don't know the answer? Thanks so much and take care.

Thank you for following up with us. There are a few points I’d like to make to, hopefully, clarify the confusion:

1.) MSU has not broadly proclaimed that people should not plant “milkweed”. As you will note in the article at the following link we recommend planting milkweed.

2.) Terminology is important. Marcia makes a very good point about this above. I’d like to add the term “milkweed” to the list of words that can cause confusion between garden center employees and customers. It is a general term for over 100 species throughout the United States.

3.) There are over 10 different milkweed species native to Michigan, each with their own characteristics. It is important to choose the correct milkweed species to grow on your property. Some milkweed species can spread rapidly by means of underground rhizomes and need lots of room. Gardeners should be cautious about planting these specific species where space is limited or other plants may have trouble competing.

4.) The species farmers battle in their fields is the common milkweed (Asclepias syrica). This is a species that rapidly spreads by means of underground rhizomes (i.e. specialized stems) and quickly outgrows areas where space is limited. Other plants in a garden setting may have trouble competing with the common milkweed. Consequently, many gardens are not suitable for the common milkweed so garden centers don’t frequently carry it. However, if you have the space, you can grow it from seed (collected yourself or purchased from a commercial supplier). Seeds need a three-month period of exposure to cold (i.e. cold stratification), so it is a good practice to plant seeds in autumn. There are several online articles about starting common milkweed from seed.

5.) The milkweed species typically found at garden centers are less aggressive and more suitable for most garden sites. All these species support monarch populations. These species include:

a. Butterfly milkweed (A. tuberosa)

b. Swamp milkweed (A. incarnate)

c. Tall milkweed (A. exaltata), and

d. Prairie milkweed (A. sulivantii).

Finally, our MSU Floriculture and Greenhouse Specialist contacted the management at Schwartz Greenhouse on Friday to discuss this topic and provide information to share with employees.

Thank you!

Thank you SO much! I appreciate this, and you.

You are most welcome! Happy gardening. :-)