It’s October and it seems everyone wants mums. Some want them for parties. Others like them on their porches. Still others add them to flowerbeds.
Mums add profuse color to any setting. Common colors are: white, yellow (the most common color), bronze, burgundy, pink and purple. Dozens of varieties are available in various shades and foliage textures.
If kept pinched most cultivars will bloom for several weeks. Pinching means removing flowers that have gone by. This usually encourages more buds to for and extends the blooming season.
I’m often asked if they’ll come back next year. I guess that depends upon what type of mums they are and how they are treated before they are planted. Like anything else, there is no simple answer.
Some mums are what we call florist mums and they aren’t very winter hardy. Most of the chrysanthemums used around here are hardy mums. That means with proper treatment they will endure the winter and begin growth again in spring.
Many people struggle when trying to over-winter mums. Usually the plants aren’t put in the ground until they are already on their way out. Plants need to establish strong root growth before cold soil temperatures set in. After planting, they also should be mulched. Mulching helps moderate soil temperatures.
Assuming your mum has had time to develop a strong root system it should come through winter in fine shape. Most varieties are hardy well north of us, so outright cold temperature kill shouldn’t be a problem. Other factors could be.
Mums need full sun or nearly full sun to thrive. They also need to be planted where they have well drained soil. Well drained in summer does not always translate into well drained in winter. Just because they are dormant doesn’t mean they can tolerate prolonged periods of wet feet.
Assuming the mums have survived winter they should be pruned back severely several times until about the middle of July. I suggest not letting them get taller than about a foot and trimming off about a third to half for each pruning session. Never let them get taller than a foot high. Depending upon the rainfall or amount of watering they will need to be clipped back about every three to four weeks.
Mums should be planted where the pH is near neutral. Therefore, they are not a good companion plant for azaleas. Mums definitely benefit from regular fertilization. Most soluble fertilizers work well.
Garden mums are what we call short-day plants. This means they form flower buds in response to an interaction of day length, temperature and plant age. All mums aren’t the same. Different varieties flower at different times in fall, based primarily on their responses to day length. That’s why you can go to the garden center and find some varieties showing virtually no color while others are in full bloom.
This light requirement phenomenon can be problematic. Planting your mums in places where there are bright lights could mean less impressive blooming next fall.
Ted Manzer teaches agriculture at Northeastern High School (firstname.lastname@example.org).