When You Should Set Out Your Mums for the Longest-Lasting Fall Flowers
Chrysanthemums often appear for sale at your local garden center or grocery store long before summer is over. But hold onto your pumpkin spice latte, should you buy these seasonal plants just yet? A favorite for outdoor fall decor, mums burst into bloom just when many other summer-flowering plants like zinnias and petunias start winding down in the cooler autumn weather. That's why a few potted mums perched on your porch seems like a no-brainer for transitioning from summer into the next season. But don't be in too much of a hurry if you want your plants to last. Even though retailers start selling mums well before fall begins, you may want to hold off on buying them just yet.
Mums prefer cooler temperatures, which can be a problem if you buy them when they're first available and it's still getting to 90°F during the day. In the heat, all the flowers will fade in only a couple of weeks so you’ll have to replace them faster if you want to keep up the colorful show through the season. If you wait until things cool off before setting out your mums, you'll be treated to blooms for up to 8 weeks once you have the plants in place. And if you get a few warm days here and there after cooler weather arrives, you can stash your mums in your house or garage until temps drop again.
Two other factors to consider: the type of chrysanthemum you're buying and where you want to use it. If you're simply hoping to use mums as an annual in a potted display or garden bed, you can opt for florist (or cutting) mums. Enjoy them until the blooms die off and then compost them.
Hardy (or garden) mums are a different story. These mums are actually perennials as long as they're properly planted and given the right care, so they make good choices for brightening up your fall garden. They're best planted in the spring once the ground is free of frost, giving them time over the summer to establish their roots in the soil before they become knockout bloomers in the fall.
If you plant hardy mums in the fall, they likely won't survive the winter. Instead, you can try letting the plants go dormant in their pots and keeping them in a cold but frost-free indoor spot like a garage until the following spring. Then you can plant the mums outside in your garden once the soil has warmed up again. You should soon see new growth appearing from the roots if your plant is still alive.
For either type of mum, when picking out plants to buy, choose mums that are still budding and not in full bloom. You'll be able to enjoy their flowers longer this way.
The bottom line is that there’s not a "best" time to put out your potted mums, but you’ll get optimal plant performance in cooler weather. Mid- to late-September is ideal if you want to love your mums for as long as possible. You can even extend your enjoyment of these plants after they die by turning them into cheery holiday decor.