If you can allow your pansy plants to remain in your garden and rest during the hottest months, they will probably begin blooming again in the fall. Shearing the plants back when they start to set seed will encourage new growth. Deadheading (cutting dead flowers off a healthy plant) will encourage more blooms. In warmer zones, pansies may look a little tired in the peak of winter, but they’ll perform beautifully when temperatures rise a bit, looking lovely in late winter and early spring.
Light
Pansies will bloom best in full sun to partial shade, but they will stay fresh-looking and keep blooming longer if grown in partial shade.
Soil
Although pansies are not fussy plants, they will grow best in loose, rich soil with a slightly acid pH (6.0 to 6.2). They are heavy feeders, so amend your soil with mushroom compost to give them a good start.
Water
Regular watering will help them hang on a bit longer, but don’t expect your pansies to last all season. Pansies prefer moist—but not soggy—soil. Make sure to use containers with drainage holes or if planting in the ground, make certain the soil drains well.
Temperature and Humidity
Pansies do not like heat at all and will begin to decline as the days warm up.
Fertilizer
As with any long-blooming annual plant, pansies appreciate some fertilizer. However, too much food will just make them leggy. They respond well to monthly foliar feeding. Use a balanced fertilizer according to the label’s directions.
Types of Pansy
If you like the variety of colors but still want a sense of cohesion, select plants from the same series. They’ll be similar in size and markings, regardless of the color.
Bolero Series: Large, ruffled, semi-double flowers; does well in both spring and fallBingo Series: Large-flowered in 14 colors from pale blue to burgundy; blooms earlier than the popular Majestic Giants seriesCool Wave Series: Fast-growing with vigorous bloom; plants have a spreading habit, like Cool Wave petunias. Good “spillers” for containers and hanging basketsFreefall Series: Day-neutral, trailing plants; great for containersJoker Series: Very pronounced faces; bicolored in complementary colorsPrincess Series: Compact growth habit and dainty flowers; monochromatic tones from cream to deep purple, with yellow centers
How to Grow Pansies From Seed
If the plants are not dead-headed, pansies will drop seeds that readily take root. In colder climates, you may find that the next spring brings a large cluster of volunteer seedlings where the old plants were located. However, most pansies are F1 hybrids, and the seeds they produce will not grow into plants that resemble the parents. You will likely get flowers that have reverted to one of the genetic parents of the hybrid. This is not always a bad thing, as you may well appreciate the surprising result. For example, a patch of pansies planted one year may self-seed into a group of volunteer Johnny-jump-ups (Viola tricolor) the next year, since V. tricolor is one of the parents of many hybrid pansies. The best way to grow hybrid pansies from seed is to buy commercial F1 hybrid seeds, which are created by hand-pollinating one species with the pollen from another species. Stratifying pansy seeds for two weeks helps improve germination. Cast the tiny seeds over a tray of seed-starting mix, moisten the tray, and keep covered with black plastic until the seeds germinate (about two weeks). Pansies need dark to germinate. Then remove the plastic and transfer the tray to a bright location and keep the soil moist. When the seedlings are a few inches tall and have at least two sets of true leaves, transplant them into small pots and keep them growing in a bright location until it’s time to transplant them outdoors. Harden off seedlings for two weeks, gradually introducing them to outside conditions, before planting outside.
Potting and Repotting Pansies
With their upright habit and pretty colors, pansies are very popular for containers and window boxes. They don’t like soggy roots, so make sure to use a relatively loose, well-draining potting mix and a container with good drainage. A slow-release fertilizer added to the potting mix is a good idea. Pinch off leggy growth and deadhead regularly, and feed the plants with a balanced liquid fertilizer every few weeks.
Overwintering
Though some varieties of pansy, such as the ice pansy, are bred to withstand light snows, expect the pansies to die away in winter. If you didn’t deadhead the pansies in the garden, you might be surprised with volunteer seeds sprouting up when spring weather arrives.
Common Pests
Slugs can be a nuisance during wet seasons, especially if growing in partial shade. Use a slug bait or thin out the planting, so it’s less damp. Occasionally, aphids will attack pansies. Insecticidal soap should remove them. Use caution if you prefer to kill aphids with a strong blast of water since pansies are rather small and delicate.
How to Get Pansies to Bloom
Pansies are such vigorous growers that they will almost always bloom well, even if their soil is lacking. However, you can encourage bigger blooms and more growth by applying a balanced liquid fertilizer once a month and switching to a bonemeal fertilizer right before the blooming season. Cut away any leggy plants to make room for more bloomers. Deadhead blooms as they die back, again, to make room for more colorful blooms in the late season.
