When speaking about fall chores involved in winterizing her garden, an experienced gardener said, "If it's brown, cut it down. If it's green, let it be." Sounds overly simplistic, but it is a great rule of thumb to apply when approaching what may seem like the huge task of winterizing your garden. It also spreads the work out over several weeks, since not all perennials or annuals will die off at the same time. Once the nights become cold and frost settles on leaves and stems of perennials, most will die and shrivel. At that point, they are no longer soaking up sun rays or delivering any nutrients to the plant. They will lose their color, appear brown and, yup, time to cut them down to the soil level.
Another way of looking at winterizing your garden is that you want to give it -- and you -- the best start in the spring. You'll want a clean slate, free from old debris and the remains of last year's annuals. Once annuals succumb to frost, they should be pulled up by the roots. By giving your garden a good fall clean-up, you'll be doing away with whatever is left of insect infestation, plant disease and giving your garden a head start for spring. If your garden has been visited by unwelcome insects, make certain to clean your garden tools with alcohol in the fall so that you're starting off spring planting with no remnants of last year's pests.
Here are some tips to make the winterizing process easy, productive and as painless as possible:
- Some gardeners tend to cut all perennials down to soil level in order to make a spent garden look somewhat tidy. And certainly withered, brown perennials, should be cut down. However, those perennials that have left seed heads, such as coneflowers and columbine, can act as a food source for local birds. You may consider holding off on cutting these down until birds have had their fill of the dried seed heads.
- Don't be in a hurry to rake up and discard fallen leaves! They can be a very cost-effective mulch for your perennial garden, helping to protect plants and shrubs through the winter. As the leaves break down, they also release nitrogen into the soil to promote strong, healthy roots.
- Annuals and vegetable plants should be pulled up by their roots and the surrounding soil removed, as well. There are diseases that can linger in the soil and pop up to infect next year's plants, if left to over-winter.
- Decide which annuals you want to keep inside for winter. Some plants, like coleus, can be started from cuttings that are taken before frost. Left in water, the cuttings will root by spring and be ready for planting. According to UNH Extension Center, annuals such as geraniums, fuchsia, lantana, begonias and impatiens can all be kept alive, indoors over winter, to be re-planted outdoors when there is no fear of frost.
- Newly planted and tender perennials and shrubs will benefit from the extra protection of additional mulch and a burlap wrap. Freezing and thawing can push new plants up out of the ground, exposing tender roots to cold wind. Use shredded leaves, wood chips or straw to mulch up to two inches deep. Mulch should be spread around the root system to insulate soil and prevent it from heaving, but not piled up against trunks of shrubs or crowns of perennials. Rose and hydrangea bushes will benefit from being wrapped with burlap to cut down on wind damage and to protect from freezing temperatures.