BLOOMINGTON, Ill. –Chrysanthemums come in a myriad of colors and flower forms, just in time to spruce up a tired flower garden or create a festive fall display. The garden centers are overflowing with these must-have bursts of color. Some gardeners have tried and failed to overwinter these mature mums bought from the garden centers. Gardening mistakes are the cause to not successfully overwinter fall planted mums states University of Illinois Extension horticulture educator, Kelly Allsup.

Gardening mistake number one is not amending the soil of the planting hole. These garden center mums are grown in a soilless media of peat, perlite, vermiculite, bark, etc. A media that is far different from the soil in your garden. This media is more aerated and has better drainage. Add 4 inches of organic matter (compost, leaf mold or well-rotted manure) to the area before planting.

Garden mistake number two thinking all mums are hardy. Plant breeders have chosen chrysanthemums for their flower color, flower form and perhaps height. With breeding comes differences in hardiness.

Garden mistake number three is improper watering. When planting chrysanthemums only tease out the roots if they are encircling. This root ball/ garden soil differentiation will cause the root ball to dry out faster than the surrounding soil even if it is amended. Check the area directly around the roots to determine if watering is needed.

Garden mistake number four is not mulching. Mulching is great insulation for the roots to make it through our Illinois winter. In the spring, gradually remove the mulch.

Garden mistake number five plant as early as you can. Plant now rather than waiting for the blooms to cease. The earliest you can plant the better root growth you will get before the ground freezes. Chrysanthemums used in fall displays and then transplanted late in the fall may not have a chance to prepare for winter.

Garden mistake number six not putting in a protected location. We know that our homes and landscapes can create microclimates much warmer than our designated zone 5b. Do not plant garden chrysanthemums in open, windy areas.

Garden mistake number seven planting near lights. Chrysanthemums bloom when the days shorten and the nights lengthen. An overhead street lamp may interrupt this process causing flower buds to not form.

Garden mistake number eight cutting back dead plants. Leaf the top growth as a form of insulation in the winter and cut back when you see new growth in the spring.

Garden mistake number nine not pinching. If you have successfully overwintered, pinch your chrysanthemums by July 4 for compact plants. Some gardeners pinch a few times throughout the garden season. This is how greenhouses and garden centers round mounds covered in flowers.

For additional questions, please contact Kelly Allsup, Extension unit educator, Horticulture-Livingston, McLean, and Woodford Unit at (309) 663-8306 or email her atkallsup@illinois.edu.University of Illinois Extension provides equal opportunities in programs and employment. If you need a reasonable accommodation to participate in this program, please call 309-663-8306