Morning Glory invasive?

(Question)

I purchased Heavenly Blue Morning Glory seeds (McKenzie) and a friend said they were invasive. My research has proven unhelpful. Some call bindweed (which I am very familiar with) Morning Glory. I do not want to plant anything that is invasive. Could you please clarify for me. Thank you!

(Answer)

Thank you for contacting Toronto Master Gardeners.  What a great question!  Heavenly Blue Morning Glory is in the same plant Family (Convolvulaceae) as Common Bindweed.  Ipomoea tricolor (the species for Heavenly Blue – commonly called multi-colored morning glory or Mexican morning glory) is beautiful and very easy to grow in a sunny spot.  I have a south-facing fence in my back garden which is covered every summer with gorgeous purple, blue, and pink morning glory blooms that the pollinators love.

Ipomoea tricolor are prolific self-seeders which is beneficial if you wish to grow them every year, but can become a nuisance as they’ll sprout up wherever the prior year’s seeds are dropped.  Two ways to avoid this: snip off the seed pods before they mature and/or pull up the seedlings or plants you don’t want when they sprout in the Spring.

Various Ipomoea species (Common Bindweed , as you mention) can be considered invasive, or a nuisance, in specific geographic locations due to their prolific self-seeding, high yields and aggressive growth. The vines can quickly wind around and cover plants in gardens and parks. However, the Ontario Invasive Plant Council does not list Ipomoea tricolor as invasive in Ontario.  But in some areas of the US, multi-colored morning glories are a prohibited noxious weed seed, and forbidden by law to be sold in some states – including Ontario’s neighbour – Michigan. A complete list of invasive species in the Midwest (including Ontario) can be found at:  Midwest Invasive Plant Network. Another US list of invasive species can be found at Invasive Plant Atlas. Your friend is correct, Heavenly Blue Morning Glories are listed as invasive – but thankfully not in Ontario.

Other resources that might be helpful for growing your seeds this spring:

Ipomoea seeds have a hard outer shell.  For faster germination, scarification (which is described in Growing from Seed – A Toronto Master Gardener Guide) works well.  I use nail clippers to take a small notch out of the seeds prior to planting.

As morning glories require support to grow, check out Trellis ideas for morning glories

Enjoy your Heavenly Blue Morning Glories this summer!