Moonflower not growing

(Question)

I planted these several years in a row and had luck only in the 1st 2 years. I nicked the seeds and soak them overnight until the hard exterior shell softens, then peel them back and put in a window planter on my balcony. They always germinate and grow except this year. In one planter, none germinate. In another planter, only 6 out of 24 germinate and the germinated plants sprout a couple of leafs for 2 weeks now but not growing. It’s been hot and humid in Toronto for the last few weeks. Not sure if I am doing something wrong considering I had luck in my previous attempts

(Answer)

Thank you for contacting Toronto Master Gardeners.

I understand that you followed the same procedure as previous years to grow these moonflowers from seed, but this year, they did not thrive.

Here are some possible causes of failure of these seeds to germinate/thrive:

  • We had snow in Toronto at the end of May. Moonflowers (Ipomoea alba) are tropical plants. They love heat. If these plants were on your balcony at this time, they may have been damaged by the cold.
  • Are you using fresh, high quality potting soil? If not, poor soil fertility or diseases in the soil may impede germination/growth.
  • How old are the seeds? Seed germination rates decline over time. If the seeds are from the same pack you have used in previous years, the seeds may no longer be viable.

Good luck with growing your moonflowers.