Szerlag: When to cut back the peonies
To cut or not to cut — that’s the question lots of gardeners ask when it’s time to put the garden to bed.
When it comes to old-fashioned peonies, the answer hasn’t changed during the years — cut herbaceous peonies back to 3 to 4 inches in height when the leaves lose their luster and turn color. Because peonies are prone to diseases such as leaf spot, all the refuse should be tossed in the trash. Putting the leaves in the compost bin risks the spread of disease. After cleaning up around the peony, you may choose to mulch with 3 to 4 inches of organic material. However, take care not to pile it directly on the plant as the soil level may increase and bury the eyes too deep, preventing them from flowering in the future. The red- or white-tipped eyes should remain 1 to 1½ inches below ground level.
Tree peonies often hold their leaves long after the deciduous trees have dropped theirs. When the peony leaves color up and begin to fall, carefully remove the dead leaves without breaking branches or damaging buds and clean up around the plant. These leaves should also go into the trash. Cutting back the stems would result in loss of flowers in late spring. They too can be mulched with 3 to 4 inches of organic material, but take care to keep it from touching the plant’s trunk.
Intersectional peonies, those that are a cross between herbaceous and tree peonies, should also have their leaves removed once they begin to fall. They are then pruned back by removing just the soft green stems. The hard, woody portion of the stem or trunk is left in place. A mature intersectional peony will have a stem of 4 to 5 inches of hardwood above ground. If you are in doubt as to what to remove, the peony pros at Peony’s Envy (peonysenvy.com) suggest leaving your plant untouched the first winter and take note what is left in spring.
According to Peony’s Envy, all peonies are exceptionally hardy and don’t need a lot of winter protection. However, mulching with organic materials helps keep newly planted peonies from heaving over the winter and enriches the soil of established plants.
Timely tip: To extend the life of your carved pumpkin, use clean instruments, spray inside and out with an anti-transpirant, such as Bonide’s Wilt Stop, put it in the garage if a hard frost threatens and light it with a flashlight.
Nancy Szerlag is a master gardener and Metro Detroit freelance writer. Her column appears Fridays in Homestyle. To ask her a question, go to Yardener.com and click on Ask Nancy. You can also read her previous columns at detroitnews.com/homestyle.