Everyone who comes to the Lewiston Area Greenhouse asks me the same question: "Are your mums hardy?"
Well...The answer is that ALL standard mums (also called GARDEN MUMS) are a hardy perennial. Hardy to Zone 5, that is, with the exception of a new hybrid known as the "IGLOO" mum which is hardy to zones 4a & 4b.
While Lewiston & our neighboring communities are in Zone 4, we CAN still have our Mums survive our winters!
It is how they are treated that make the difference.
Why SOME Mums Don’t Last Through Winter: Potted mums from the grocery store, big box store or farmers' market usually don’t survive cold winters. They are NOT BRED to be hardy; they are being sold for their SIZE, form & color. Think of them as disposable holiday decor.
INSTEAD: Buy your mums from a greenhouse. The time to plant mums is really in early August (or sooner if you can!). The mums at the Lewiston Area Greenhouse (and most other greenhouses) are either over-wintered for a 2nd season OR planted in MID-JUNE. They have a fully developed root system inside their pots when you buy them. Still, you must get them IN THE GROUND as soon as you can if you want to give them their best chance at a return next season.
Mums in full flower don’t put energy into growing more roots to sustain the plants through the winter so be sure to buy mums with some unopened buds. Generally speaking, after October 1st is too late for in ground planting. Plants put in the ground from mid to late-October won’t make it through the winter in areas where temperatures dip into the single digits. Temperatures regularly dipping below zero can cause you to lose even spring-planted, hardy mums to winter without some care & protection.
Want to give your mum its best shot at overwintering and returning next year? Follow these tips: Plant them as soon as you buy them!!!! Leave the dead foliage on the plants until spring. An unpruned plant can survive at much lower temperatures. Mulch the entire area surrounding the root system. Add 4 to 6 inches of mulch after blooms have faded and before the ground has frozen completely for even more protection. Water them, even after the blooms have faded, until the first freeze. As soon as the thaw happens next spring, water them but don't uncover them from their mulch nest until after the average last frost date. As they begin to re-emerge in the spring, mums really don't need to be shaped/pinched but if you insist on that "perfect" circle shape, never pinch them after July 10th and only sparingly before this date.
Featured Garden Mums Show 1st Bloom between September 1st-16th (approx.)