Winterizing Your Garden, Part Two

Caring for Your Shrubs, Roses and Grasses

Last month we focused on how to care for your perennials as part of winterizing your gardens. This month we'll highlight what you can do to protect your shrubs and roses from the damaging wind and cold temperatures of winter.

Let's start with Grasses:
•Many gardeners do nothing in the fall to their grasses. Leaving grasses standing for the winter provides visual interest and some color to the winter landscape. Whether good or bad, grasses left standing also provide some shelter and protection for birds and other animals from the winter weather.

•Grasses are more tender than we think. In the past, if you have cut your grasses back in the fall to discover the following spring that your mound stayed brown, never greened up and the grass didn't come back at all, then you've experienced winter kill. By leaving the grass standing over the winter, the outer grass stalks are protecting the inner stalks of the grass plant which is your new growth for next spring.

•If you leave your grasses standing for the winter and plan to trim them next spring, a good way to tell when it's time to trim them, is to look for new, green growth in the center of the plant. This new growth will be your indication to trim away the old grass.

•If you do decide to cut down your grasses this fall, leave 10-12 inches of the plant standing, do not cut grasses down to the ground. The standing grass will help the plant to overwinter better.

Shrubs and Evergreens
•Smaller evergreen trees and small to large evergreen shrubs loose moisture all winter through their needles. Continue to water all evergreens up to when the ground freezes and consider spraying your evergreens with Wilt Pruf protective spray. It is a light, fragrance free polymer that's sprayed over the entire evergreen to lessen moisture loss. Wilt Pruf can also be used on your Christmas tree, wreathes, swag and other greenery to keep them from drying out.

•Rhododendrons also benefit from an application of Wilt Pruf. This broadleaf evergreen shrub should never be pruned in the fall. The flowers are developed on old wood so any pruning in the fall will eliminate the flowers for next spring. It is a good idea to water your rhododendrons up to when the ground freezes. Rhodies are shallow rooted. Their roots spread mostly horizontally versus going deep into the soil. A layer of mulch around the shrub will greatly help the shrub preserve moisture.

•Hydrangeas, Rose of Sharon, Caryopteris, Lilacs, Holly, Butterfly Bush, Forsythia, Weigela and Viburnums all benefit from a late season watering before the ground freezes. Moisture is the main element that shrubs use to protect themselves against winter conditions. Mulching around these plants also helps them retain moisture.

•Hydrangea buds are very sensitive to cold. So if you have an old wood hydrangea it is a good idea to wrap your hydrangea for the winter. Remember, old wood hydrangeas set blooms in the fall for the following spring. So if the buds produced in the fall are frozen in the winter, you will not have blossoms in the spring.

•Ordinary burlap can be used to wrap hydrangeas. After the first hard frost and when leaves have fallen off the hydrangea wrap burlap around the plant and fill it with leaves or mulch. This provides insulation for the plant and protects the buds so they will overwinter into next spring. Never use plastic to wrap your hydrangeas. Plastic unlike burlap doesn't breathe so when warmer winter days arrive, the plant cannot breathe and can warm to such high temperatures the plant cooks inside the plastic and dies.

Roses
•To help roses better prepare for the winter, it is important that they start going dormant in early fall. Stop fertilizing your roses by mid-August and stop deadheading around October 5-6. Stopping both of these processes slows down the plant's growth and its energy to produce new flowers is lessened.

•Double Knock Out Roses are bred to be hardy from Zone 4-9. We are in Zone 5. These roses have survived our winters without being wrapped. However if your Knock Out Roses are planted where they will be hit by North and West winds throughout the winter, you might want to consider wrapping them in burlap and filling with mulch.

•Hybrid tea roses usually require winter protection. Wait until a hard killing frost has caused most of the leaves to fall. Prior to covering or wrapping the rose remove any remaining foliage. Though "hilling" of soil to a height of 10-12 inches from the base of the rose up is common winter protection, hilling often erodes during the winter. Wrapping the roses in burlap and then filling the bottom 10-12 inches with soil and the rest of the space with leaves, straw or mulch is more likely to provide better protection of your roses.

•Rose cones are popular. The keys in using them are not to cover the plants too early and the cones need to be well ventilated to prevent heat build up. Punch 5-6 holes around the top and bottom of the cone. Place a brick or rock on top of the cone to weigh it down.

ALL roses should be watered well before the ground freezes