How to Grow Winter Pansies, a Cold-Hardy Plant That Will Fill Your Garden With Color

Winter pansies (Viola hiemalis), also known as ice pansies, provide beautiful color in the garden come fall and winter. They come in a range of shades, from blues and purples to reds and pinks, making them a popular choice for gardeners looking to add interest to their garden during colder months. In mild winter locations (USDA zones 7, 8, and some parts of 9), they'll bloom continuously. In colder areas (USDA zones 4, 5, and 6), winter pansies will bloom in fall and go dormant during the coldest days of winter.

How to Plant Winter Pansies Outdoors 

If you're planting winter pansies in the ground, choose an area that gets at least six hours of sun and has well-draining soil with a lot of organic matter, says Linda Langelo, horticulture specialist at Colorado State University. Pansies should be spaced anywhere from 7 to 12 inches apart. Plant winter pansies outside in early spring or late summer, depending on your climate. 

1. Push on the bottom of the pot and gently tug at the base of the pansy to remove it from the pot. 
2. Dig a hole that's as deep as from the bottom of the roots to the crown. 
3. Place the plant in the hole. 
4. Backfill the hole with soil and tamp down. 
5. Water the plant well. 
6. Add a layer of mulch. 

How to Grow Winter Pansies From Seed 

Growing winter pansies from seed is relatively straightforward and can be done indoors or outdoors. 

Growing From Seed Indoors

It's easiest to start pansy seeds indoors or in a protected area and then transplant them outdoors. "Start the seeds about eight weeks before your area's average first fall frost date," says Justin Hancock, horticulturist for Costa Farms. "Transplant outdoors when they have at least four pairs of leaves and temperatures stay below 80 degrees Fahrenheit or so."

1. Fill trays or pots with a seed-starting mix. 
2. Sprinkle seeds over the soil and cover them with a 1/2-inch layer of seed-starting mix. 
3. Water the seeds well. 
4. Cover the seeds with plastic. 
5. Keep the seeds in a warm location (ideally around 70 degrees Fahrenheit). 
6. Move the seeds to a location with bright, indirect light once they start to germinate.
7. Remove the plastic wrap. 
8. When the seed grows its second set of true leaves, transplant it into a small, 2-inch pot. 
9. Water so they're consistently moist and keep in a bright location. 

Growing From Seed Outdoors

You can also sow winter pansies from seed outdoors, which is best for milder regions of the country. The best time to do this is late July or early August. "It takes up to six weeks for them to have a good root system," says Langelo. Choose a location with six hours of full sun and well-draining soil. 

1. Gently till the soil. 
2. Place the seeds about 5 to 10 inches apart. 
3. Cover with soil lightly. 
4. Water regularly. 
5. Add a light layer of straw mulch to help keep the soil moist (optional). 

How to Care for Winter Pansies 

Winter pansies are relatively easy to care for so long as they are given full sun and adequate water. 

Light

Winter pansies do best in a spot with at least six hours of direct sun (or bright, indirect light indoors). "They'll survive shadier spots, but they won't bloom as well," says Hancock. "In full shade, they may not bloom at all."

Soil

These plants prefer well-draining soil that's rich in organic matter. "If your soil is on the poor side, amending liberally with compost can really help them," says Hancock. 

Water

Winter pansies prefer moist but not wet soil. "If you've got winter pansies in a pot, they might need a little more water than in the ground, but be sure not to over water," says Ryan McEnaney, garden designer and author of Field Guide to Outside Style: Design and Plant Your Perfect Outdoor Space. "If you're wondering if they're in need, stick your finger into the soil to the second knuckle. If it's dry, give them a good soak. If the soil is moist, leave them alone for now."

Fertilizer 

Fertilize winter pansies every two weeks with 15-30-15 fertilizer. "The phosphorus (30), the middle number, stimulates root development and helps the plant mature, making for a better-quality of flowers," says Langelo. "It also assists in disease prevention."

Temperature

Pansies prefer temperatures that range from 40 to 60 degrees Fahrenheit. "While winter pansies bloom while temperatures are cool (typically below 60  or 65 degrees Fahrenheit), they don't want to get hit by a hard freeze or deep frost," says McEnaney. "The most damage can come from big swings in temperatures, so if you're going to have a steep drop off, especially overnight, cover them with a sheet, towel, or organic material like pine straw. Because they're cool season crops, they do not tolerate lots of humidity."

How to Grow Winter Pansies in Containers

Winter pansies also grow well in containers. "I would recommend placing them in containers that you can move inside to protect them from the extreme winter weather," says Langelo. Be sure the container you grow them in has holes in the bottom before adding soil.

1. Fill the soil just under the rim of the pot.
2. Remove pansies from their current container.
3. Dig a hole that's as deep as the distance from the bottom of the roots to the crown.
4. Break apart the root ball so the roots don't continue growing in the same direction as they were in the pot.
5. Place pansies in the hole. Space your pansies anywhere from 1 inch apart to 8 inches.
6. Fill in around the roots with soil and tamp down around the plant.
7. Water pansies well and regularly to help them get established.
8. Add a layer of mulch around them, especially if you live in a colder climate.
   

How to Prune Winter Pansies

When winter pansies are in bloom, you can remove spent flower heads by pinching them with your fingernails or trimming the stem back with clean, sharp pruners. "This allows the plant's energy to be put into developing new flowers instead of helping old ones limp along," says McEnaney. "If any part of the plant starts to stretch out and look wonky, just cut it back by about one third and allow it to grow back in."

How to Propagate Winter Pansies

One way to propagate winter pansies is through cuttings, says Langelo. To do so, you should use small pots that are about 2 inches in size.

1. Fill the pots with well-draining soil mix.
2. With sterilized scissors or pruning shears, cut below the leaf node where the leaf meets the stem.
3. Place the cutting directly in the potting soil. 
4. Place the cuttings in an area with bright light and keep the soil consistently moist.
5. Once it has roots, transfer to full sun. Keep the plants in a cool environment of 60-65 degrees Fahrenheit.

How to Overwinter Winter Pansies

Winter pansies are hardy enough to survive colder temperatures so you won't need to go extra lengths to keep them alive. "In cold climates, a layer of mulch or other winter protection is an especially nice added blanket to protect from swings in temperatures," says McEnaney. "Be sure to keep watering your winter pansies until a hard freeze. If you're in a warmer climate without consistent freezing temps, provide sporadic watering so they don't dry out."

Common Problems With Winter Pansies

Although winter pansies are relatively low maintenance, there are some common problems you may encounter when caring for them.

Pests

Aphids and slugs are two common pests you may encounter when caring for winter pansies. "A trick to get rid of slugs is placing a small amount of beer in a shallow dish buried about ground level," says McEnaney. "They're attracted to the beer and will drop into the dish, leaving your pansies alone." Aphids can be treated by applying insecticidal soap or an insecticide containing neem oil to the foliage of your winter pansies.

Yellow Leaves

Yellow leaves are typically a sign of overwatering. "It's easy to accidentally overwater," says McEnaney. "Just back off a bit and don't let the ground get too saturated. Some yellowing leaves might drop off, so just make sure to get them out of the garden so disease doesn't develop on the fallen leaves."

Yellow leaves may also be a sign of Cercospora violae, a disease that's specific to pansies. "This disease is caused by warm and wet weather," says Langelo. "It starts on the lower leaves of the pansy. This occurs mainly in the southern region of the U.S."

Brown Leaves

Brown or black leaves could also be because of improper watering. Check the soil to make sure it's moist but not soggy, and adjust your watering schedule accordingly. "Browning leaves could also naturally happen later in spring as temperatures rise and the plant starts to run its course," says McEnaney. "If it's getting hot and you're battling brown leaves, it's ok to give it a prune back and let other plants take over for the warm season."

Darkly colored leaves may also be a result of the fungus Colletotrichum violae-tricoloris. "This appears as spots that are in a concentric ring pattern that turn grey or brown with a thick black margin," says Langelo. "Warm and wet weather can cause this in late spring and fall." The application of fungicides when you first notice the disease will help control the spread as well as the removal of infected plants and plant parts.