The Difference Between Perennial and Hardy Mums
Mums are confusing. We buy them late in the year, plant them in the ground and wait for their return the following season only to be left waiting and waiting wondering where they may be.
The garden center employee told us they were ‘hardy’ and yet they still have not arrived for our next season of enjoyment so off we go to buy some more. If this sounds like a familiar yearly experience for you then let me explain why your mums Fall return is so darn unpredictable.
‘Hardy’ mums came from cross-breeding perennial mums with showier mums that are used in the cut-flower industry. Perennial mums come back reliably every year but the mums grown for florist arrangements were typically grown in greenhouses and did not need to survive the winter. By cross-breeding these mums, we now have the large array of colorful ‘hardy’ mums that are on the market today. Unfortunately this means that while they are ‘hardy’, they are not perennial and the likelihood of them surviving winter is small. This doesn’t mean however, that they can’t come back every year.
So what is the trick for getting your mums to come back?
The obvious answer is to plant perennial mums. The difficult part in that answer is where to find them. This is hard not only for you, the gardener, but (as a plant buyer for a nursery) for me as well.
The next best option?
Oftentimes we buy the mum, put it in our containers until it is done blooming and then plant it in the ground late in the season. The problem with this is that the roots are shallow and do not have time to establish a deeper root system before the freezing winter. This means that the earlier you can get your mum into the ground and growing, the better. Spring and early summer would be the best time for planting to develop the root system but ‘hardy’ mums are rarely available at that time. So the next best, and unfortunately last option, is to plant your mums as early in the fall as possible and know that they may or may not survive to the next season but when they do…they will be spectacular!