I had a number of mature wingstem in my garden last summer and fall. I don’t see any coming out. Do they surface late?
Also, I collected a lot of wildflower seeds (e.g. wingstem and others). They haven’t been hardened in the cold. Can I sow them now or do I have to wait for fall?
Thank you for contacting the Toronto Master Gardeners with your question.
Wingstem (Verbesina alternifolia) is a robust perennial that prefers moist soil conditions with full sun or partial shade. Wingstem usually bloom from August to October which would explain why you have not yet seen them coming out. This plant is known to self-seed extravagantly so do not delay in dead-heading or you may have hundreds of plants next year! The seeds can be sown at any time and germination can sometimes be quicker if kept at 15 to 20 degrees. It is preferable to either plant them outside in the fall for the next season or to cold-stratify to plant in the spring. The seeds require cold-stratification for 30 days to germinate successfully. Good luck!
I’ve included two links with some useful information on growing wingstem.