While many roses, shrub roses in particular, can tolerate cold temperatures
without special protection, winterizing hybrid tea roses is a critical
maintenance practice to ensure vigorous growth from year to year.
There are several things you can do to make sure your hybrid tea
roses survive northern winters long before the cold winds blow.
First, choose the most winter hardy roses available to plant in
your rose bed. Next, make sure your roses are healthy and not under
stress; healthy plants have a better chance of surviving the winter
than weak plants. Reduce stress on roses going into the dormant
season by irrigating adequately in late autumn and discontinuing
nitrogen application in late summer or early autumn.
minimum winter protection, tie canes of bush roses together, then
mound soil 8 to 10 inches high around canes. For maximum winter
protection, cover the rose bush with a protective cylinder. Use
straw, leaves or similar material to insulate the bush inside the
cone. Puncture several one inch holes around the top of the cone
for air circulation.
Teas, grandifloras and floribundas should be protected from winter
damage after a killing frost but before the soil freezes (most shrubs
do not require special attention). Reduce breakage of tall canes
by winter winds by cutting them back to 30 to 36 inches and tying
tips together. Remove dead and fallen leaves around the plants.
Hill soil over the center of the plants in broad rounded mounds
at least 12 inches high and 12 inches wide. Cover the soil mounds
with a mulch of leaves, straw, boughs or similar material.
method consists of using all mulch--wood chips, sawdust, shredded
hardwood, or pine bark--instead of soil, mounded to 15 to 18 inches.
Some gardeners prefer to construct wire mesh cylinders to surround
each plant, which they fill with mulch. Still others use rose cones,
baskets with bottoms cut out or burlap to wrap the plants.
winterize climbers, remove them from their support. Lay them on
the ground and cover with 3 to 4 inches of soil. If this cannot
be done, gather the tips of the stems together, tie them and wrap
in straw with a wrapping of burlap over that. The base of the climber
should be covered with 10 inches of soil. When severe winter weather
conditions have subsided, remove most of the mulch and soil from
around the bases of plants. You may leave a 2-inch layer of mulch
in the bed.
from Cindy Welyczkowsky and Jane Martin, Ohio State University Extension,