Experts Offer Tips on Putting the Garden To Bed

Summer's blooms have almost all faded away. The tomato plants are nearly done producing for the season. The leaves on trees are beginning to turn. And geese are flying overhead, honking out their goodbyes. For the gardener, those are all signs that it's time to begin putting the garden to bed for the season. From cleaning out beds to collecting seeds, and spreading mulch and manure to oiling tools, there is plenty to be done. To help with a to-do list, we asked a handful of area garden experts for advice. The work involves a lot of chores, but the best part is, it's still time spent in the garden.

CLEAN & CLEAR

Nurserymen and women agree: "The main thing with any garden is clean-up," says Gordon Kenneson, horticulturalist at in West Hartford. 

"The biggest thing is cleanliness," says Kevin Cavalieri, owner of in West Hartford.

"The number one thing I would recommend from the standpoint of disease control in the garden is sanitation," says Joan Allen, assistant cooperative extension educator at the University of Connecticut in Storrs. "Remove all dead plant material from the garden, whether it's ornamental plants or fruits and vegetables. Dead plant material is an important overwintering site for many plant pathogens and a source of spores that can cause new infections in the spring."

But don't cut too much, says James McInnis, horticulturalist at the . He recommends leaving plants that add "winter structure." Plants including ornamental grasses, butterfly bush, and sweet autumn clematis are just a few that add to the character of a winter garden and can be pruned in late winter, if desired.

Also take care that you "don't cut perennials too early," says Sheila Wells, an employee of Comstock, Ferre Co. in Wethersfield. Plants with seed pods such as coneflower and sunflower provide birds with much-needed food.

As gardeners clear out the beds, they may wish to "collect seeds," says Barb Pierson, nursery manager at White Flower Farm in Litchfield. "Many of your favorite annuals such as zinnias and cleome can be collected in the fall, stored in a paper envelope in your cabinet and sown next spring."

Plant material should be composted unless it shows evidence of disease such as black spot or powdery mildew, experts agree. Place any diseased plant material in bags and put it in the garbage.

When it comes to removing autumn leaves from your garden beds, "don't go crazy raking your garden beds or your shrub borders," says Pierson. "Leaves make great mulch and mimic the natural layer of leaf litter that helps retain moisture and provide protection.  A thin layer is best — less to remove come spring and not enough for rodents to use as bedding."

VEGETABLE GARDEN

In the vegetable garden, "As soon as plants stop producing, pull them out by the roots," says Wells. Early in autumn, consider planting cool weather crops including kale, lettuces, and spinach, she says. Summer's herbs can be cut and then dried or frozen. Wells freezes basil in ice cubes, which can be added to sauces simmering on the stove.

When the clearing and clean-up of the vegetable garden is done, "add manure," says Cavalieri. Sold in bags at most nurseries, manure breaks down over the winter and its nutrients nourish new seedlings and plants in spring. "It's really the only time to add manure," says McInnis.

It's also a good time to add lime, which takes five to six months to alter soil PH, says McInnis. "Our native soils are in the 5.5 PH range in Connecticut. Lawns and vegetable gardens prefer a PH of approximately 6.5," he says.

Individuals with large vegetable gardens might consider planting a cover crop such as winter rye, buckwheat or oats to help retard weed growth, says Wells. The cover crops die back after frost. 

MULCH

"Mulch beds if you haven't already to insulate root systems," says Cavalieri. Shallow-rooted specimens such as rhododendrons are particularly vulnerable. Also at risk are specimens planted late in the season. "Frost heaves can push them out of the ground," says McInnis.

It's important when mulching that you do not surround and suffocate the trunk or stem of a plant. Do not build a mulch "volcano" around the trunk, McInnis says. He recommends that gardeners spread mulch around the base of a plant then use their fingers to clear it away from the trunk or stem.

"Avoid using too much mulch in boggy areas," says Wells. "It promotes fungus and mold." 

PROVIDE COVER & SUPPORT

For plants like rosemary that aren't designed to weather winter in Connecticut's Zone 6 climate, you can improve their chances of wintering over by adding a layer of protection. "Take a peach basket full of oak leaves or a hoop of wire [filled with oak leaves] and put it over the plants," says McInnis. Oak leaves, which are waxy, don't break down over the course of the winter. The layer of insulation they provide "adds about a zone of protection," he says. "Do it in mid-December and take it off in mid-March." 

Last year's record snowfall resulted in a lot of breakage in the garden. In case we're in for a repeat, consider "tenting" shrubs including ilex (holly) and boxwood. "They can benefit from a burlap or fabric wrap," says McInnis, "especially if they're exposed to northwest winds." 

Shrubs positioned below a roof can be victims of avalanching snow or roof-raking. Consider covering those plants with wooden sandwich boards so snow slides off.

Multi-trunk shrubs such as arborvitae are known to split under the weight of heavy snow. Tie their trunks together loosely using rubber tubing.

ORNAMENTAL PRUNING

While pruning roses is best done in spring, you can cut them back now in areas where the canes are not wanted, says Kenneson. If a rose is overgrowing its site or creating a thorny hazard, prune away those branches, but avoid major pruning. 

Pierson issues a caveat: "It may be tempting to give shrubs a severe haircut, but in many cases you could be removing next spring's flowers or in the case of a rose, exposing canes to more winter kill."  

LAWN CARE

Fall is a good time to fertilize the lawn. "If you only do it once a year, fall is the best time," Kenneson says.

The same goes for putting down lyme on the lawn, says McInnis. 

CONTAINER POTS

Many homeowners change their container pot plantings for the new season. Autumn annuals including chrysanthemums, cabbages and grasses are popular. Newer additions to the marketplace include autumn pansies.

As temperatures drop toward winter, leave pots outside only if they are made of materials designed to withstand freezing, says McInnis. Most ceramic pots are vulnerable to cracking. (Water gets in crevasses and expands, and the result is a chipped or broken pot.) 

Keep in mind that plants in containers are especially vulnerable to winter's cold temperatures. Plants in the ground are insulated and warmed by the earth, but plants above ground are not. "If there's an insulation of snow, the temperature at ground level is about 34 degrees [Fahrenheit]," says McInnis. "If there's no snow, the ground temperature is whatever the air temperature is." One of the few plants that can survive winter above ground in a pot is the dwarf Alberta spruce, the small shrub you see in grocery stores around Christmastime. 

EQUIPMENT CARE

Before stowing your pruners, clippers, trowels and other tools for the season, dip them in a bucket of oily sand, says McInnis. He recommends keeping in your garage a bucket of sand mixed with a bit of motor oil. "Plunge the tools in a few times, wipe them down with a cloth, and it will keep them rust-proof," he says.

Hoses should be drained, curled up and put away, he adds. Proper dry storage prevents cracking and breaking when winter's freezing weather comes.

If you have fuel-powered lawn and garden gear – from lawn mowers and leaf blowers to weed whackers – run the engines dry, or the fuel will gum up the machinery, says McInnis.

PLANT BULBS

Nurseries and catalog companies are now fully stocked with a great selection of bulbs for spring. While some garden experts recommend waiting until after first frost to sink bulbs in the ground, others say earlier planting helps them get settled. "You can plant them any time now," Kenneson says. "Get them in, get them watered, and they'll be established." 

McInnis agrees. "Even if they sprout growth, they seem to stall, and they do just fine in spring."

"Scatter some bulb food where your bulbs are planted," says Pierson. "This is why I always leave a plant label so I can remember where they are." 

HYDRATE

Plants and bulbs should go into the winter season well-watered to avoid dehydration. Last year's dry weather combined with a long winter stressed a lot of rhododendrons, and there was a lot of die back, says McInnis. If Mother Nature doesn't water the garden throughout autumn, remember to keep the hose handy.

NO- NO's

We'll say it again: Do not prune spring bloomers such as rhododendron, lilac and andromeda, which have already set their buds for spring. If you prune now, you're sacrificing spring flowers.

Do not prune trees or shrubs at this time of year or it encourages them to send out new growth, caution Pierson and Wells. 

TO FERTILIZE OR NOT

While there are some who recommend fertilizing perennials and shrubs before winter, the general consensus is to wait until spring. Fertilizing plants now is like giving them caffeine before they go to sleep. Better to provide that boost just as next year's growing cycle commences.

"Fertilization in the fall traditionally has applied to trees and shrubs," says Pierson. "In that case, the tree or shrub must be dormant or past active growth so that late tender growth is not forced and then killed during winter. So, a late August fertilization would not be recommended but a late November one would. For perennials, the same rule applies in that the plants should be dormant before a fertilizer is used.

"My preference for fertilizer is late winter for trees and shrubs and early spring for perennial beds," says Pierson. "I like being able to get out in March and use Hollytone on my evergreens and a granular for larger specimens. For mixed borders I generally will use compost covered with mulch (SweetPeet) after I see the plants start to emerge and I'm good for the season."