How aggressive is Evening Primrose?

Asked June 17, 2019, 6:38 PM EDT

Is Evening Primrose ‘Siskiyou Pink’ too aggressive to put in a flower bed? I came across this plant at a major nursery chain. It was advertised as blooming all season long. Those claims were backed up by most plant info websites. They are listed as having a spread between 12-18” so I happily put them in my perennial garden this spring. I’ve recently come across some videos online where a few landscapers spoke out heavily against the use of this plant in landscapes saying things like “once you introduce this plant you’ll never get rid of it” and “It’ll take over the entire bed” or “It certainly can’t be kept in one neat spot.” Are these comments accurate? I don’t mind it spreading a bit as long as I could pull out the unwanted saplings each spring. I would be miserable if I had to add 10 minutes a week to my weekly weeding just to keep this plant reigned in. So, given my situation and location (full sun, southern exposure) should I remove this plant before it becomes unmanageable?

Washtenaw County Michigan

1 Response

Hello, Pink evening primrose or Oenothera speciosa is not native to Michigan but rather is native to the grasslands. It can be aggressive in the perfect setting and if that should be the case, you would have to divide and separate. You would have to observe it and decide whether you can tolerate its aggressive behavior should it become aggressive in your garden and remove it if it is too much work for you to control.