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Over the Garden Fence

This Weather and Bulbs

We have had our first real taste of cold weather over the last few days. Maybe your tender plants escaped being damaged, but others were not so lucky with the forecasted temperatures in outlying areas of low 30s and even high 20s.

This has been a “warning shot” to get any houseplants and tropical plants indoors. Houseplants really do not do well with nighttime temperatures in the 40s anyway and why research recommends they be placed indoors before the furnace even comes on. This allows them to acclimate to lower light and humidity levels slowly.

This cold snap has put summer bulbs and tubers at risk as well. Given our growing season, plants in this group got off to a slow start with too much water and cooler temperatures that went way too long into the spring. I had not seen a single planting that has showed any signs of slowing down before the cold weather showed up. It is a lot easier to deal with storing summer bulbs if the soil is dry and the tops have not been frosted off. Bulbs should be dug and allowed to dry down before storage. Often times it is the Canna bulb foliage that is the first to go down with damaged tissue starting from the top down with foliage that turns discolored and black. Besides the popular Canna, Calla lily and Amaryllis are planted in our beds and will need to be dug up. While not a summer bulb, impatiens being very succulent also is easily damaged by cold frosty weather leaving us with a pile of mush to deal with.

The tops of summer bulbs and tubers need to be removed leaving about two inches of stem above the bulb or tuber. Shake most of the soil off and place in a cool dry location for a few days before storing away for the winter. Using a flat, place the bulbs and tubers right side up, putting as many as you are comfortable with next to one another. Cover most of the bulb with potting soil to conserve bulb and tuber moisture, and place them in an area that will remain above freezing, but not so warm that they will start to grow before we are able to set them back in the garden next spring. Check on them about once a month and if too dry add just a bit of water. If not soil, other choices might be peat moss that is only slightly damp or sawdust. Just avoid anything that can hold excessive moisture that can cause the bulbs to rot and something that can be worked into the garden soil.

A note on hardy spring bulbs. It is not too late to get them planted for a beautiful bloom show next spring. Don’t be one of those “should have, could have” gardeners next spring wishing you had planted those hardy bulbs!

About the author: Richard Hentschel’s expertise extends across several subject areas with specialties in lawn care, fruit tree production, woody ornamentals, and home and community gardening. During his 45-year career in horticulture and agriculture, Hentschel became a well-known and respected expert for commercial and homeowner audiences, industry organizations, and media. He retired from University of Illinois Extension in April 2022 with nearly 30 years of service as a Horticulture Specialist and Educator in northern Illinois.