Daylilies are beautiful perennial flowers that are famously low-maintenance, so many gardeners and flower-lovers choose to include them in their flower beds and gardens. Perennials are dormant in the winter, but they still need some care and a proper winter environment to survive until spring.
Here are 8 tips on how to overwinter daylilies in pots:
- Choose a daylily that is suitable for your climate.
- Make sure you put your daylilies in large enough pots.
- Store them in an unheated room if you live in a cold area.
- Bury the pot into the ground and cover it with leaves.
- Insulate the pots with mulch.
- Turn the pots on their side.
- Don’t overwater.
- Check on your plant regularly.
Let’s take a closer look at each of these tips so you’ll be equipped with all the information you need to successfully overwinter your daylilies.
1. Choose a Daylily That Is Suitable for Your Climate
First and foremost, set yourself up for success by choosing a daylily appropriate for the climate in your region.
You have three different options for daylilies:
- Dormant, which are deciduous
- Semi-green, which may or may not retain its foliage through the winter
- Evergreen, which retains its foliage through the winter
To know which daylily is best for you, you’ll need to know your U.S. Department of Agriculture Plant Hardiness Zone. These zones are a standard by which growers can determine which plants can grow in a certain location.
Once you know your zone, you can decide which daylily is right for you:
- Dormant grow in zones 3-9
- Semi-green grow in zones 5-11
- Evergreen grow in zones 8-11
To give yourself the best chances of keeping your daylilies alive through the winter, select the right kind of daylily for your zone. Those in warmer climates will have the most success with evergreen and semi-evergreen daylilies, and those in colder climates should stick with dormant daylilies.
If you buy your plants locally, you shouldn’t have a problem finding the right daylily. You’ll need to be more careful if buying online.
2. Make Sure You Choose Large Enough Pots
Daylilies can survive in pots, but only if they have enough room. Full-sized daylilies shouldn’t be in any pot smaller than a gallon (3.8 L).
A one-gallon (3.8-liter) pot is the absolute smallest a daylily should be in, especially if you are overwintering the plant in a pot. Larger pots can contain more soil, which helps insulate the roots. I would recommend at least a five-gallon (22.7-liter) pot for overwintering.
You should also remember that ceramic pots will crack if left outside, so you should use plastic pots when overwintering your daylilies outdoors. Ceramic pots should be okay if kept in an unheated garage.
3. Store Them in an Unheated Room if You Live in a Cold Area
It is possible to overwinter daylilies in pots outdoors. Still, if you live in an area with an extremely cold climate that is highly susceptible to frost, your daylilies might have a better chance of surviving if they are in an area where they are more protected from the elements.
Frost can be especially damaging to all kinds of plants, such as daylilies and lilacs.
If you live in an area with a USDA zone 7 or lower, you should put your pots in an unheated garage or basement. Getting the daylily out of the immediate cold helps prevent winter damage.
You can move the pot outside again once there’s no threat of frost.
4. Bury the Pot Into the Ground and Cover It With Leaves
If you live in a USDA zone 8 or higher, you can leave your potted daylilies outside throughout the winter. I suggest burying the pot into the ground to insulate the roots and covering the plant with 3 inches (8 cm) of leaves for even better insulation.
Ground heat rises from the earth all winter, so the daylily will be much warmer underground than above the surface. After winter, you can remove the leaves and take out the container.
You can also wrap the pot in bubble wrap to provide extra insulation, but do not wrap the entire plant in plastic, as this will limit the daylily’s ability to get oxygen and kill it.
5. Insulate the Pots With Mulch
Regardless of whether you are keeping the pots indoors or outdoors, you can insulate the pot to prevent repeated thawing and freezing, which is often the cause of a plant’s death. Insulation helps keep the soil at a consistent temperature, so the daylily’s roots don’t get too cold or get so hot that the plant wilts and dies.
You can use styrofoam insulation in some planters, but I recommend using leaves and mulch instead. Simply put several inches (5+ cm) of mulch in the pot around the base of the stem of your daylily. Depending on wind and other winter conditions, you may need to replace the mulch from time to time, so keep an eye on your plants.
I recommend using cedar chips for daylilies. In addition to providing insulation for your plants, this mulch will also absorb any unpleasant odors, so if your daylily does begin to rot, the mulch will block the smell. You can also use this mulch as pet bedding if you have some leftovers!
6. Turn the Pots on Their Side
If you keep your pots outside, you risk having water from rain or snow accumulate in the soil. This can create crown rot, which deteriorates a plant’s root system.
A soil-borne fungus causes crown rot. This fungus can survive in the soil indefinitely, and it is encouraged by wet conditions.
Once a plant has crown rot, there is little you can do to save it. As it progresses, your daylily will wilt and die. Crown rot is also difficult to notice in its beginning stages, especially if you are overwintering a plant and not necessarily checking it every day.
Water can also accumulate because of the freeze-thaw cycle that occurs during winter. In cold weather, the soil in your pot freezes, and when rain or snow falls, the water can’t drain.
The best way to prevent this is to turn the pot on its side. This prevents any issues with standing water.
7. Don’t Overwater
You probably won’t have to water your daylilies during the winter, and you should especially avoid overwatering, so your daylilies don’t get infected with the dreaded crown rot. However, if you check your daylily’s soil and it is bone dry, it is okay to add some water, but only enough to keep the roots moist.
8. Check on Your Plant Regularly
When you’re overwintering a plant, it can be easy to forget about it for weeks on end. However, you must check on your daylilies regularly.
You should pay attention to your plant and do to the following:
- Check if any insulation you’re using is holding up.
- Feel the soil to make sure it isn’t bone dry.
- Inspect the plant for signs of crown rot.
Daylilies are hardy flowers that can last through the winter in pots as long as they are cared for properly and given the right winter environment. If you’re dedicated to keeping your daylilies alive to reawaken again in the spring, follow these tips for the best results.