I have some elegance ranunculus corms that I purchased in March 2020 but did not plant until this year. 9 out of 10 corms sprouted but only two are flowering. They are planted in large containers, in a sunny location, since I plan to remove the corms in the fall to overwinter them. Is there a chance more will bloom next year, or should I consider them lost and start a new next year?
Hello, thanks for contacting the Toronto Master Gardeners. Ranunculus are so beautiful! One of the most attractive of all flowering bulbs (in my opinion), but unfortunately they are a challenge to grow well in our climate. They greatly dislike heat and humidity preferring a long cool spring. They also cannot tolerate our winters, so corms must be lifted and brought inside to overwinter. You mentioned the delay in planting out your Ranunculus corms. This may have effected their vigour. Usually any bulbs should be planted within a few weeks of receiving, however if your corms remained firm and fleshy, they should still be viable, and the fact that they mostly all sprouted was a good sign. My advice would be to remove the flowers and allow the foliage to die back naturally. Keep the soil moist but not soggy. Remove foliage once it had browned and stop watering. Once completely dry, store corms in a cool dry spot for the winter.
One tip I received from a gardener who has good luck with these plants is to soak corms for a few hours in slightly warm water before planting out.
I have included a link to a post from a Master Gardener colleague who has provided good detailed information on the proper care of these plants. Good luck – hopefully next year you will have an abundance of these beautiful blooms.