In many regions of the country, tucking your perennials in for the long, cold winter requires the spreading of a protective blanket of mulch. Doing this will help your plants resist the temptation to wake up during premature warming periods and put out growth that will only be damaged when cold weather returns. An insulating blanket of mulch can also help keep perennials that are borderline-hardy or cold-sensitive to overwinter more successfully.
When spring arrives, and the threat of ice and frigid temperatures recedes, many gardeners find themselves wondering, “Should I remove the mulch?” and “If so, when?” and “Can my perennials just push their way through? When do I remove mulch from perennials in spring? Or should I just let them push up through it on their own?”
The answer to those questions depends a lot on why you mulched those particular plants in the first place, but here are some things you should consider when figuring out the ifs, whens, and whys of removing a blanket of winter mulch. Some perennials will successfully break through a barrier of mulch, but more often, damage will result. If the vegetation has to struggle to push up through a layer of coarse mulch, doing so may take a toll on its initial appearance. Even if a covering of mulch does not completely smother a plant, it can disfigure its foliage and stems. While no permanent harm is done, this does temporarily affect their beauty.
Ask yourself these two questions to keep from taking a chance with the health of your perennial flowers:
What kind of mulch did you use last fall? If you applied mulch made from coarse material, such as large, unshredded leaves, you generally want to remove that layer manually as early as possible in the spring—especially if the mulch has tamped down over the winter, forming an impermeable barrier. You will want to take that off as well as soon as the weather is moderate enough and the threat of severe cold has passed.
Has the threat of severe cold or a hard frost passed? Getting the timing right for mulch removal also requires you to be a keen observer of your plants and the climate/weather conditions where you live. Keep a garden journal from year to year to help you remember when your freeze and frost dates are. Consult it when spring seems to be on the horizon. Walk your garden and see if the ground is thawing out. When the air is warmer and the threat of severe cold is behind you, this is the perfect time to remove that mulch from your perennials. Leaving the winter blanket in place is likely to smother them or encourage the growth of harmful mold—removing the mulch will allow your perennials to grow and thrive.
Taking the insulating blanket of winter mulch off your perennials will allow them to breathe and grow. Once they have achieved a bit of height, re-apply a bit of mulch around them to inhibit the growth of weeds. Try some lightweight shredded leaf material; they will suppress weed growth and add valuable nutrients into the soil as they break down.
Gardening is both an art and a science. There are general rules that vary by zone and region, but a lot of what you should do and when for your plants depends on your good judgment and knowledge of your own varietals and microclimate. When spring is here for good, you’ll feel it in your bones. Act accordingly. Your perennials, and everything else in your gardens will soon be pushing up new growth and preparing to supply you with grace and beauty for another year.