Posted on: November 11, 2016 | Written By: Doug Oster |
The bright orangish-red leaves of a fothergilla shrub are one of the stars of the four-seasons garden right outside Linda Hyatt’s office window.
“It’s wonderful,” she says about her view, which also includes a fenced-in vegetable garden. She’s the master gardener coordinator and extension assistant in horticulture at the Westmoreland County Penn State Extension office in Greensburg. The campus of the extension office includes a perennial garden, annual garden, herb garden, vegetable garden, composting area, the four-seasons garden and much more. As the season winds down, Hyatt explains the three things she thinks are most important when preparing the garden for winter.
“Sanitation, soil testing and covering the garden, whether it’s some kind of mulch or cover cropping,” she says.
In the perennial garden, her team of volunteers cuts back many of the plants.
“Stuff that’s diseased goes to the trash,” she says. “The rest to the compost.”
The next step is to pull out any weeds that have been hidden under and around the perennials. After that’s done, she’ll still occasionally walk around pulling things that might sprout late, such as chickweed or bittercress, so they can’t get established.
All the annuals also are removed, but the space doesn’t stay fallow long. Master gardeners split perennials, put them in pots and sink the pots in the soil, which insulates them for the winter. Many of those plants will be used for their plant sale the next spring.
There are many ways to put the garden to bed though. Some gardeners want to leave perennials and other woody plants standing to help wildlife — either as a seed source or for a place to hibernate for the winter.
“It’s OK to do that,” Hyatt says of leaving plants up. “That’s how I do it at home. We don’t do it here just so that it’s done for the season and gives us a good start for spring. It’s also about aesthetics here and for many gardeners at home, too. We want it to look cleaned up.”
This is also the prime time of the year to test the soil, she says. “If you do it in the fall, for one thing, the lab isn’t as busy.”
If you need to add lime, phosphate or potash, November is a good time to do it, she says. Because these soil additives take time to work, getting them on now makes sense. The frost and thaw cycle will break them down and make them available sooner.
It’s important for gardeners to get a scientific number when dealing with soil additives so they know how much is needed. “If your pH is too low or too high, then some nutrients are not available to the plants,” Hyatt says.
Soil tests are available in person at any extension office for $9 or can be ordered by mail for $10. Complete instructions are included on how to take samples and send them to the Penn State lab. Results are then sent back to the gardener. She also welcomes people to the office if they need help interpreting the paperwork and can access your results on a computer to talk you through understanding them over the phone. You can reach the office at 724-837-1402 or here.
All the gardens at the extension office will eventually be mulched. The raised beds in the vegetable garden are most important, she says, because everything grown there is donated to the Westmoreland County Food Bank. Last year, the garden produced nearly 1,000 pounds of vegetables.
The beds all get a good layer of compost, made on site. If root crops will be grown in beds, that compost is turned over; if not, it’s just laid on top.
“All those beds out there in the vegetable garden are strictly compost. It’s organic matter; it improves your soil structure. You have good microorganisms in there, micronutrients. That’s their preferred way to garden out there,” Hyatt says.
The soil amendments also will be used to mulch the other gardens. It’s one way to add fertility, retain moisture and avoid erosion.
A nice touch in these gardens are the mailboxes, which are decorated by an artisan volunteer. Each one holds gardening information for visitors.
There are lots of plants that are left up in the garden. Milkweed pods crack open to reveal soft white silk that will carry the seeds away in the slightest breeze. Milkweed is a great pollinator plant, especially for monarch butterflies.
An area called an insectary is untouched and filled with plants for beneficial insects and pollinators. Luminescent yellow tansy flowers are covered in honeybees and other insects. The ornamental grasses stand tall as the low angle of the sun streams through the panicles of seed heads.
“We leave the grasses up for winter interest. They look just beautiful,” Hyatt says. “They’ll be all over the place come spring, but we’re used to that and we’ll just clean them up then.”
Micah Tribou, operations manager at Plumline Nursery in Murrysville, cuts his grasses down in the fall.
“The reason I do them now as opposed to in the springtime is because over the winter, those grass blades will start to break loose and they will end up all through your yard,” he says.
He’s removing what’s left of leafy perennials, such as peonies and hostas, when they turn yellow to brown, as a way to reduce diseases. Out in the nursery, perennials are trimmed back, and he’s even making more of them.
“It’s a great time of the year to start splitting perennials,” he says.
“Any time you have something freshly transplanted, I always recommend mulching in the fall,” as a way to protect the root system as winter looms, Tribou says. “It’s not so much about the weather being cold, you don’t want that shift in temperature to be dramatic, so we’re trying to insulate that root system.”
He’s even cutting up those ornamental grasses if they show signs of being crowded. When the center of the plant becomes hollow he gets to work with a sharp, flat-bladed tree shovel. “What I do is I dig the whole thing up and then I cut the middle out,” he says of the arduous job. The remaining plants are put back in the soil, watered and mulched.
Although the garden is being closed down, there’s still time to add something and usually for a bargain. He’s in the process of moving trees and shrubs into large cold frame tunnels to give them some protection before putting them in a landscape. “If you’re planting that deep into the season, you have to make sure that root mass has not been exposed to these crazy temperature fluctuations,” he says.
Another thing he recommends homeowners do is cut the grass after leaf removal. If it’s left long, the lawn can be susceptible to fungal diseases and other problems. “Get one last cut, make sure it’s nice and low and uniform, you don’t want to scalp it,” he says. “Whatever you think looks good at mid season, that’s basically the length you want to have it going into the winter, don’t let it grow tall.”
Protect the roots of existing trees and shrubs with mulch, too, never on the trunk though and don’t fertilize either, he says. “That fertilizer could push new growth, that’s going to do some serious damage when the cold weather shocks it.”
Plants that are marginally hardy like crape myrtle can be protected with a spray called Wilt Pruf and then wrapped in burlap. “Wilt Pruf is made from pine sap and it protects the plant from dehydrating too quickly. It’s especially effective when it comes to evergreens,” he says.
To try and coax blooms from his hydrangeas next year, Tribou surrounds them with stakes which that attaches burlap to, leaving the top open to allow snow and rain in. “There’s an added benefit too, it keeps the deer off,” he says with a laugh.
Doug Oster is the Tribune-Review home and garden editor. Reach him at 412-965-3278 or email@example.com. See other stories, blogs, videos and more at everybodygardens.com.