In the Garden:
Graham Thomas rose can be grown in a container and overwintered in a garage or shed.
Overwintering Potted Roses
I used to think roses were the domain of gardeners who had lots of room, formal gardens, and a regular spray schedule -- none of which fit my style. I admired the blossoms and swooned over the perfume, but roses weren't for me. Then one spring I saw a cute little number -- pink with ruby-edged petals and a sweet scent -- at a nursery and thought, "I'll just enjoy it for the summer and then say goodbye." In the fall when the leaves fell off I thought, "I'll just try to keep it a little longer."
So I moved it to the garage, wrapped it in burlap, and stored it in a cupboard along with pots of bulbs I was forcing. I watered it occasionally during the winter when I watered the bulbs. To my delight it put out new growth in the spring, and I was hooked.
For years I never put a rose bush in the ground, I just kept them in pots. Now I have rugosas, climbers, and landscape roses planted in my garden but I still have several potted roses that I overwinter in a garden shed attached to the garage. I lose one now and then, but I've lost them in the ground as well. Even one winter's long, frigid spell didn't do in my potted 'Sea Foam' rose tree.
I admit to feeling rushed even at the end of the season, and I don't always do what's best to protect my plants for winter. But do as I say, not as I do. Here are some techniques for bringing your potted roses to the other side of winter.
Preparing for the Big Sleep
Treat potted roses like any other roses in early fall. Stop cutting flowers and let the hips form. This signals the plant to slow down and prepare for winter. The cell walls thicken to protect against winter injury, but all you'll notice is the stems turning purplish and the leaves dying. In late fall, pluck any remaining leaves -- every single one -- from the plant and remove any leaves and debris from the soil. Old leaves can harbor disease and insect eggs, and those left on the plant can cause increased moisture loss at a time when it's not easily replaced.
Some experts recommend spraying the branches with a dormant oil spray or a fungicide. You can mix your own mild fungicide solution of 1/3 cup baking soda in 1 gallon of water. I may try a dormant oil spray this fall to see if it will reduce the sawfly larvae damage in spring. Those little green worms come early and then leave, but they make quick work of skeletonizing the foliage.
Keeping Plants Cozy
Since you'll be wrapping your potted rose in a cocoon of sorts, a little pruning and branch shortening will help. Remove diseased, damaged, and crossing branches, and cut back long canes to a manageable length. Then bring the pot into its winter quarters -- a shed or garage where temperatures remain cold but not arctic. In an ideal situation, temperatures wouldn't drop below 20 degree F, but I know my shed gets colder than that and plants still survive.
To wrap plants, I usually use burlap or sheets or even plastic bubble wrap. If I'm using a burlap bag, I'll set the pot inside it and stuff the bag with leaves or straw. I'll wrap the branches separately with more burlap or a sheet, securing it with staples or twine. Then I'll stuff straw gently around the branches.
Don't try to make the cocoon too tight because roses are prone to rotting and fungal disease if they don't have adequate ventilation and drainage. The goal is to insulate the root zone within the pot (highest priority) as well as the branches. Leave an opening in the wrapping so you can reach in to check soil moisture and add water as necessary. Check if temperatures rise above freezing or at least a couple of times during winter.
Since cold air settles near the floor, raise your pot up on a table or place it inside another larger pot or planter. An empty half barrel provides ideal protection, with hay or straw stuffed in between the barrel and the pot.
If you don't have a good winter shelter, you can overwinter potted roses outside. In fall dig a hole in the garden that will accommodate the pot. Make sure it's not in a low spot where water and cold air settle. Submerge the pot in the soil, cover the crown of the plant with about a foot of wood chips, then cover that with straw. You can also use other protective enclosures, such as chicken wire cages, just like you would with in-ground roses.
One of my favorite benefits to overwintering potted roses is that I can take advantage of fall sales, even though it's not the best time to be planting roses in the ground. And since many roses are putting out a last flush of flowers in fall, you can still see and smell what you're getting.
Care to share your gardening thoughts, insights, triumphs, or disappointments with your fellow gardening enthusiasts? Join the lively discussions on our FaceBook page and receive free daily tips!