FrontRangeLiving.com -> Garden -> Winter Garden
COLORADO WINTER GARDEN
Winter allows Colorado gardeners to restómuch like their gardens. But our
approaching winter, coming after a summer drought, has forced gardeners to
reconsider time-honored approaches. Horticultural experts are suggesting that we
leave perennial beds alone, allowing the top growth to bend over and protect
roots throughout the dry months. Applying mulches, winter watering and
establishing a compost bin all take on an urgency. This winter, more than
ever, requires planning for spring.
ALLOW PERENNIALS TO SHELTER THEIR ROOTS
Although some gardeners have cut back perennials and shrubs as a matter of
fall cleanup, this may be the year to let your perennials shelter each other.
Nature encourages grasses and shrubs to sweep over one another as a winter
blanket. Precious moisture is conserved and dry winters lose their ferocity. The
birds will thank you, too, since seed heads and rose hips provide winter food.
"Leave your perennials to catch more
snow," says Robert Cox,
Colorado State University horticultural agent for Jefferson County. "Like snow fencing, you can do
a bit of water harvesting. Another school of thought believes that all the snow that
ends up on the foliage evaporates before it reaches the ground. So you can cut
back halfway to the ground. Either idea is valid."
Harriet MacMillan, horticulturist at Echterís Greenhouse in Arvada, adds,
"I only remove the tops of foliage if there is an excess of debris. Unless
you can see that snow will not get down to the roots of the plants, you can
leave the foliage."
The plants best suited to survive a dry winter are drought-resistant. That includes Colorado native plants as well as the exotic ornamentals
like Russian sage (Perovskia 'Blue Spire'). Many of the Mediterranean herbs are hardy, too.
Culinary sage is still useable in the garden nowóthe perfect accompaniment to holiday feasts. Thyme,
oregano and mint will persevere through dry spells and even parsley, which
requires much more water, will stay
green for harvesting long after other crops have died.
Marilyn Raff, author of "The Intuitive Gardener," adds compost
during the winter to her perennials. "I try to give up to six
inches of compost around the roots of shrub roses. But the grasses I leave until March, then I
cut them from six to 12 inches to rejuvenate them," she says.
CLEAN UP THE VEGETABLE GARDEN
In contrast, a vegetable garden left unattended through winter provides a
cover for pests and disease. Itís still recommended that kitchen gardeners
dispose of tomato vines and other plant debris that may protect the egg sacs of
insects. But stripping the soil of all covering without snow is a recipe for
erosion, so try planting a cover crop of rye, vetch or clover. Itís not too
"They will green up and grow in the spring," says Carol OíMeara,
Colorado State Extension assistant horticultural agent for Boulder County,
"and although rye usually is the quickest to germinate, they will have such
a long period of striation through the winter that any of those would be
okay." Striation is a period of cold that is required for some seeds to
TREE CARE: WRAPS, WATER, MULCH
Most gardeners are bracing for another summer of drought. But we
may also have a winter of drought. Dry winds and meager snowfall are sure to
damage trees and shrubs. "We are still recommending hand watering for
shrubs and trees," Carol says. Some tips will help trees to survive a
tough winter and prepare for a difficult spring and summer, too. The website www.watersaver.org, sponsored by the Denver Water Board and CSU Extension gives
information on winter care for shrubs and trees.
Robert also recommends tree wraps for non-native young deciduous trees along
the Front Range. Sunscald will damage a young tree up to three years of
age. Usually found on the south or southeast side of a tree, the exposed trunk
will appear bleached in spots. "Sunscald is not a problem in other parts of
the country, but a tree wrap is beneficial here. Our day temperatures can be in
the 60s and the tree will try to come out of dormancy. Then at night when
temperatures drop below freezing, the tree will try to go back into
dormancy." Wraps can be applied in late November and removed in March.
City trees like lindens have fared poorly, Robert says, while hawthorns,
flowering pears and hackberry trees remain stalwart. His major concern is for
the native ponderosa and piŮon pines. Both pines are drought-tolerant but four
years of accumulative drought have weakened these tough mountain trees. Winters
may be no better than summers when it comes to ongoing dry spells.
"Winter can be even more harmful to trees than summer," Robert
says, "Cold, dry spells are terrible for trees and shrubs. Water during an
extended dry spell, say, three or four weeks." In the metro areas, youíll
have to use a water device that is designed strictly for tree watering. Any
sprinkler system has been banned.
MULCH, COMPOST AND DRIP IRRIGATION: THE NEW COLORADO GARDEN
Consider mulch to be your gardenís best friend in both winter and summer.
Robert prefers bark mulch of varied sizesólike the chipped bits that come from
tree trimmers. Pebbles, he says look nice "but hold the heat and make the
plants warmer than they would be otherwise. The stuff that you buy bagged called
bark mulch is expensive and the wind blows them. You can put down the mulch of
tree trimmers about two and a half inches thick and cover that by more expensive
mulch if you like that look."
Harriet never covers her perennials with mulch but simply spreads
the mulch around the plant. "Perennials have a basal foliageódonít
cover that. Check perennials every four to six weeks and water as needed. We are
learning that we donít have to water as much as we once did, but we must water
If you plant spinach seeds for an early spring harvest, or bulbs such as
tulips, they will require regular watering all winter. Try to water when the
temperature reaches 40 degrees. Otherwise, water will not filter through the
soil but lie in a frozen pool on top. This is true for trees and shrubs as well.
In spring, expect to hear about drip irrigation. Farmers on the Western
Slope are using drip irrigation for their wine grapes. Melon farmers in Rocky
Ford have turned to drip irrigation, too. They dropped their use of water by 30
percent and gained a bumper yield. Drip irrigation is perfect for vegetable
gardens, perennials, trees and shrubs.
And Robert says it may even by used for lawns, but will first be adopted by
vegetable gardeners. "Instead of the hose being flat like the old soaker
hose, drip irrigation hoses are round and porous to water. Itís great for
vegetables because you can configure the hose to any way it fits your garden.
Drip hoses donít last a long time in sunlight. Thatís why itís recommended
that they be covered by wood chip mulch."
And finally, set up that compost bin that youíve been meaning to get to.
This is the perfect winter chore that will yield wonderful results in the
future. Despite all the complicated literature out there, itís remarkably
easy. A wire bin will do. Fill it will leaves from the yard and kitchen
vegetable scraps. Lemon rinds and pineapple peelings will take longer to
decompose than tealeaves and coffee grinds. But eventually they will break down
and provide terrific compost.
You'll soon discover that thereís never quite enough compost for your needs.
Marilyn buys compost by the truckload and spreads it throughout her garden all winter long.
Winter gardening doesnít demand as much from us as the vigorous growing
season, but thereís work to be accomplished. Marilyn recommends checking on
the garden periodically for water needs, or to cut back a shrub or ornamental
grass as needed. Perennials like Joe Pye weed (Eupatorium purpureum) might be cut back half in winter,
then cut more severely in the spring. "It can be a gradual process,"
she says, about pruning, watering and mulching, "thereís plenty to do in