by Connie Oswald Stofko
Canna lilies are tall, impressive plants that I’ve long admired in Western New York gardens. So when I visited the Master Gardener plant sale in Buffalo this spring and saw a whole area with cannas, I toyed with the idea of actually buying one.
When a helpful Master Gardener explained the different varieties, I admitted I was hesitant to buy a canna lily because I’m a lazy gardener. I know you have to bring in the bulb for the winter.
The Master Gardener smiled and told me I didn’t have to do that.
“You can treat it like an annual and buy another one next year,” she said.
I actually hadn’t thought of that. I checked out the price and bought one.
In this article, we’ll talk about overwintering plants or bulbs, that is, keeping them in a dormant state and then reviving the plant again in spring. We’ll also take a look at bringing plants inside and trying to keep them growing all winter, or at least for a few extra weeks.
And I’d love your comments on which plants you overwinter and which you don’t bother with. Please leave a comment below.
Decide which plants to bring inside for winter
Let’s start with plants you don’t bring inside for the winter. You don’t have to worry about plants that are perennials in Western New York, such as hostas, daylilies, roses and coneflowers. They tolerate our cold winter temperatures and even need a period of cold to be healthy, so don’t bother trying to bring them inside.
Then there are houseplants. We call them houseplants because we use them inside our houses, even during the winter. If you set your houseplants outside for the summer, you will need to bring them back inside. Care for them as you have in the past. Tip: When you bring houseplants inside, make sure to look for pests.
The plants we’re talking about are plants you bought for your garden. They are plants that won’t survive our winters and won’t come back on their own next year. You would have to buy again next year if you don’t bring them inside. (We often refer to these as annuals, although in the warmer area they come from they are perennials.)
David Clark, CNLP, who teaches the great horticulture classes at the Buffalo and Erie County Botanical Gardens, shared some ideas with me. There are no hard-and-fast rules about which plants you should overwinter or exactly how you should care for the plants during the winter.
“Experiment!” Clark said. “What can you get to work?”
Here are some guidelines to help you decide which plants you should bring in for the winter.
Plant is expensive
If you paid $50 for one plant, you probably want to overwinter it, Clark said.
And if you paid $10 or $20 for a plant and you want to fill a garden bed with lots of those plants, that will be pricey, too. Try overwintering those expensive plants.
Plant is important to you
If you’ve been searching for years for a plant and it’s rare, try to overwinter it.
“I have an eight-year-old passion flower that is precious to me,” Clark said. “It’s a Russian variety. I really baby that thing.”
Process is easy for you
For Clark, it’s fun to overwinter all kinds of plants, but if it’s too much work for you, you don’t have to do it, he said.
You may feel bad about throwing, say, healthy dahlia bulbs on your compost pile instead of trying to overwinter them. If so, buy a different plant! There are many that will work just as well in that spot.
You have proper conditions
If you want to overwinter bulbs or plants in a dormant state, you need a cool, dry area, such as a basement or sunporch. If you don’t have an area that, you don’t have the proper conditions.
If you want to keep tender plants growing inside through the winter, you need proper lighting. A sunny window isn’t going to be enough.
“The brightest window in your house equals the shadiest spot in your garden,” Clark said. He has a basement full of grow lights. “The limiting factor is the amount of light you have. If you don’t have enough light, the plants will get spindly and lanky, and the bugs will like them.”
For some plants, you would need a greenhouse to keep them growing all winter.
How to overwinter tender plants
Let the plant go dormant in a pot
For plants such as caladium, lantana (which Jim Charlier from Open Gardens overwinters) and passion flower, you can just keep the plant in its pot.
Find a cool spot, such as a basement or sun porch. Ideally the temperature would be between 40 and 50 degrees Fahrenheit, Clark said.
Once a month, water the plant sparingly. You don’t want the root or tuber to totally dry out. On the other hand, you don’t want to soak the soil so heavily that water comes out the bottom.
Store tubers outside the pot
Previously we published an article on overwintering tuberous begonias. This method will also work for plants such as dahlias, elephant ear (alocasia and colocasia) canna lilies and gladiolus. Also see a discussion about overwintering geraniums here.
Keep the plant growing until spring
Keeping the plant growing through winter is a little more difficult than putting it into a dormant state.
Pat Gurney, who shared her Orchard Park landscape on Open Gardens, mentioned she wouldn’t bother bringing coleus in for the winter because it would be weak by spring. I share her sentiment because I don’t have even a sunny window, much less grow lights.
Clark disagrees. Every year a friend of his took cuttings and propagated them by placing the cuttings in water on a windowsill.
“I think it’s a worthy plant to bring in,” he said. It’s super easy to propagate the cuttings and coleus does well in shade. See more about coleus– cuttings, propagating & getting it through the winter– in this article. Make sure you read the comments, too.
With the help of grow lights, Clark will attempt to keep a five-foot tall lemongrass plant growing inside all winter. Even if it doesn’t grow all winter, he can at least use the herb in cooking for some weeks or months.
Plants to bring inside for a little while
You can extend the growing season a bit for some plants by bringing them inside.
Bring in pots of marigolds, zinnias, impatiens and other annuals to get a few more weeks of enjoyment from them, Clark said. An alternative is to cut some stems from the plant and use the flowers in a vase.
You can also keep many herbs, such as rosemary, marjoram, tarragon, oregano and chives, growing inside for some time, he said. If you have an under-cabinet flourescent light in your kitchen, you might be able to keep them growing longer than if you just set them in a window.
Clark leaves parsley outside because it’s a biennial. It grows from seed the first year, and when the plant wakes up again in spring, you will get more leaves before it flowers. But if you want fresh herbs for cooking, bring it inside.
Vegetables and fruits can get an extended life inside. See this article on bringing your tomato plant inside.
If you have very good light, such as tabletop grow lights, you might even be able to grow strawberries (Fragaria vesca), Clark said. No, you won’t get many berries as you would outside, and the berries you get will be small, but it’s fun to be able to eat fresh strawberries in winter.
What plants do you overwinter or bring inside for a few extra weeks of enjoyment? What plants have you decided not to bother with? Please leave a comment below.
Cheryl, thanks for that suggestion!
I bring my potted impatiens in and take cuttings to root in water all winter. I still get some blooms to brighten up the sun porch.
Hi Sue, it’s interesting that you use Wandering Dude (the newer name for Wandering Jew) as a tropical plant outside on a porch. I think of them only as houseplants. Thanks for all that information!
I take cuttings of scented geranium and Tradescantia (aka: Wandering Jew). I’ve had good luck rooting them in water or potting soil. If I go with soil, I use rooting hormone to give them a good start. I keep them in a sunny window till May and then out to the porch as temps permit. I store Cannas, tuberous begonias, glads and oxalis in dry peat moss. I bring them in with their foliage, after shaking off excess soil, and let the foliage dry up before cutting off and just storing the bulbs/roots. For geraniums, I dig them and shake off the soil and lay them on trays in the garage covered with paper or another tray. I start them in potting soil around the end of March under lights in the basement along with the begonias. I plant Oxalis and glads directly in the ground or pots when temps will stay above 50F
Hi Karen, this is a good question to ask the Master Gardeners in your county. I hope that helps.
Thanks for that tip, Meredith!
Paula mentioned that it can be hard to get cannas out pots and I agree! My method is to trim back the foliage then tip the whole pot onto a tarp. I can easily get all the tubers out then put the dirt back into the pots. I use the large pots for “heeling in” little misc pots that need protection. I’d love if anyone has tips about wintering over fuscias.thanks
Hi Meredith, yes, it’s better to share healthy plants with other gardeners than to toss them on your compost pile. But sometimes it is a bit too difficult and time consuming to save every plant. I do try to find good homes for my extra hostas, but sometimes it’s just too much to pot up the extras and keep watering them until I find someone who wants them. Yes, extra hostas have gone on my compost pile. Hostas and canna lilies aren’t native to Western New York, so I don’t think our ecosystem will miss them. I don’t feel guilty about placing an ornamental plant in the compost. Having said all that, I have been heartened by all the comments here and I’m going to try to overwinter my cannas.
Wow! I am amazed by all these stories, all these methods and all the plants that everyone is bringing in for the winter. One thing that I never thought about was that if you bring plants or tubers in, the plants might actually come back bigger and better!
Greetings friends! I have to say I hate the distinction of what plants are “valuable” enough to save! Yes, you can buy new canna tubers every year
but isn’t that just supporting our horrible replacement economy? 35 years ago a neighbor gave me red canna lilies; over the years I’ve shared them with friends and neighbors and seen them passed along to other happy gardeners. Shouldn’t that be one of the reasons we garden? Hostas were originally called “ friendship plants” because they were so easy to share. Most gardeners that I know have at least one story to accompany a
Gifted plant and that makes them “Valuable “ in my mind. If you have plants you can’t keep or don’t have room for please try to pass them along. I like to think that as involved gardeners we are also Earth stewards. Please give plants the respect they deserve as part of our eco-system.
I moved here from San Francisco and had no idea how to garden in 4 seasons. Last fall, there were perennials (b.e.susan’s/shasta daisies/hens&chicks/japanese maples & a few other strays) that I didn’t have time to get into the ground. My next door neighbor, a gem of an elder, told me- ‘just put them in the garage up off the ground & wrap some newspaper around them, they might be ok”. I was mystified. The garage? no true light? no water? what??!
Sure enough though, in the spring when I unwrapped…everyone had tiny little buds and continued to flourish. It felt like Xmas morning! I still just can’t comprehend this but am tickled pink that mother nature clearly knows what she is doing even if I don’t now that I am a New Yorker. I’m ashamed to say some *still* are not in the ground (I was taking care of my mom who just passed) but I am not deterred. If I can’t get it done before winter – back to the garage they will go & I have a sneaking suspicion I may be elated just one more time!
We bring in our elephant ears, caladiums, and oxalis bulbs, put in dry pots, and then brought out in spring/ late May. Worried they wouldn’t make it, but they did this past winter/ year. Also , our Turkish fig tree goes in our unheated garage before snow flies and I put snow on it or lightly water every three weeks to keep it from drying out. Figs come back every year and we are eating the harvest today in Buffalo! Lastly, Vinca Vines can be put in the ground from hanging baskets, etc. in the fall and they will survive our winter in Buffalo. Then in the spring I dig them up and have great plants ready to go. Now I don’t spend money on them and can spend elsewhere:)
I overwinter my geranium. Take it to the basement- I don’t water it at all. Seven years ago it started in a 4” pot, less than a foot tall and now it’s in a 12” pot and about 3 feet tall.
I have four tropical hibiscus bushes (16-20 years old), a bougainvillea (15 years old), fuschias (up to 10 years old), a teenage lantana, passion flower (12 years old), several walking iris (3 generations), Xanadu Philodendron (6 years old), Boston Fern (4 years old) that all spend the winter in two areas of our attic under plant lights. In addition, I have several tuberous begonias, dahlias, and elephant ears in pots that get brought in and go dormant in their pots. The oldest of those is a six year old deep orange tuberous begonia.
I dig out calla lilies and store them in bushels of straw in my cool temperature basement for replanting in the spring. Started with one pot and have expanded to 7 large pots. The hardest part is getting the bulbs out of the pots.
I dig up Cannas, Calla lilies, Four O’Clocks, Elephant Ears and Dahlias, dry them out and store in cardboard boxes covered in shredded papers, in my basement. As soon as the ground is workable they go out in the garden. By the time they come up the threat of frost is past. Any other plants come inside unless they are definitely annuals (Cleome, Cosmos, Zinnias). I have many tropicals, palms, ferns and tender perennials including lantana, begonias and passion flower that I bring in. I am fortunate enough to have access to a building with many south facing windows and they do very well. I even have a Meyer’s lemon tree that produces lemons for me every year!!! I have a hanging basket of million bells that gets trimmed back and it has been re-blooming for me for over five years!!! Obviously everything doesn’t make it but I figure why not give it a try!?!?
I have a Mandavilla that my mother gave me the year she died (2018). I keep it under grow lights in the winter. It usually gets a bad case of aphids so I spay it as needed. I’m thinking of changing the soil because it’s probably tired after 3 years. Wondering if I should do it now or wait to spring???? The plant is important to me
I bring my large pots of Rex Begonias in to the living room in the early fall, and they go back out in the shade of the patio in mid-May. They get good light but no sun inside, and are watered weekly, with the houseplants. In the spring I give them a fertilizer boost with Miracle Gro
I have a little floating island of pitcher plants that I keep in my garden pond in the summer. I put them in a tub in my unheated garage, and they survived the winter beautifully.
Last winter I brought in Dahlia tubers and they did wonderfully well. Stored them in peat moss in a dark basement, Had twice as many flowers this year as last.
I have over wintered many varieties of elephant ears for years. They just get bigger & better every year. They are stored in my basement with grow lights & I water them sparingly. They get pretty pathetic looking but once I bring them outside in late spring, they grow bigger & better. Might try Lantana this year. Persion Shield didn’t make it last season but I’m always open to try it again.
Dahlias and Canna bulbs get dug, dried, and stored in open plastic bags of sawdust. They get a sprinkle of water into the plastic bags, followed by a little rifling thru each bag at Christmas and Valentine’s day. In March, I removed the bulbs and show no mercy if there are any brown spots, they get trimmed off. I start a 12 cannas of each color, and all the dahlias in 6 inch pots and they live under. 16 hours per day of high fluorescent light in the basement greenhouse tables. It’s important not to start them in huge pots, they will grow so big that they break when transplanting. Everybody comes out under the oak tree or porch about May 20, and each set of pots gets 2,4,6, then 8 hours of indirect sunlight on successive days for about 2 weeks. Replant and label, water based on what the plant endured over the last 24 hours. Never water based on upcoming weather. Fertilize at planting, and once during the season in July.
Thank you for sharing, I want to try this.
Maxine, good luck!
Coleus. I take cuttings from the plant, root them in water and then plant them in soil. When they begin to outgrow their pots, I take cuttings from these plants and begin the process again. I have beautiful foliage all winter and an early source for new cuttings and plantings in the spring.
This summer we bought a gorgeous caladium called Miss Muffett (I bought it for the colors as well as the name). I’m anxious to try overwintering it. Wish me luck.