Common Name Snow-in-summer, silver carpet, mouse ear, chickweed, dusty miller
Botanical Name Cerastium tomentosum
Family Caryophyllaceae
Plant Type Herbaceous, perennial
Mature Size 6-12 in. tall, 9-12 in. wide
Sun Exposure Full
Soil Type Loamy, sandy, well-drained
Soil pH Acidic, neutral
Bloom Time Spring, early summer
Flower Color White
Hardiness Zones 3-8 (USDA)
Native Area Europe

Snow-in-Summer Care

Here are the main care requirements for growing snow-in-summer:

  • Space snow-in-summer plants 1 foot apart to avoid the overcrowding of these fast-spreaders.
  • Plant in an area that gets full sun, receiving at least six hours of sun a day.
  • Place snow-in-summer in relatively poor but well-draining soil.
  • Avoid planting snow-in-summer flowers if you live in a humid climate.

Light

This plant prefers full sun conditions. Snow-in-summer can develop fungal problems if planted in the shade.

Soil

Snow-in-summer thrives in well-draining and slightly acidic (pH 6.0 to 7.0) soil. However, the plant adapts to most soil types except those that are damp and poorly draining, which can cause root rot.

Water

This plant prefers relatively dry conditions and has a good tolerance for short periods of drought. It will not do well where frequent rainfall or watering keeps the ground soggy.

Temperature and Humidity

Snow-in-summer likes relatively cool, dry summers. It will be very short-lived if planted in hot, humid climates. However, snow-in-summer is salt-tolerant and does well in cooler coastal regions.

Fertilizer

Snow-in-summer generally does not need any type of special feeding; it prefers rather poor soils. If your snow-in-summer isn’t performing well, help it out with a fertilizer that’s high in phosphorous and applied right before your plant blooms. Follow the product label instructions to use the proper amount.

Types of Snow-in-Summer

  • ‘Silver Carpet’: This snow-in-summer features a more compact flowerhead and is slower to spread.
  • ‘Yo-Yo’: Here is a compact snow-in-summer cultivar that produces abundant blooms and spreads less aggressively.
  • ‘Columnae’: This plant has features similar to ‘Silver Carpet’ but is a lower-growing plant, forming 4-inch mounds, and it also spreads less aggressively.
  • ‘Olympia’: This cultivar grows in clumps reaching 6 to 8 inches tall and up to 18 inches wide with upright flower stalks.

Pruning

Avoid rampant spreading by shearing the flower stems off before the seeds drop. Trimming can be done easily with a lawnmower that’s set high or using a string trimmer. Then, carefully clean up the debris that’s cut away to prevent it from reseeding. Some cultivars are more compact and less likely to spread uncontrollably.

Propagating Snow-in-Summer

Snow-in-summer can be divided and replanted to create new plants. This division method is best done immediately after the plants have finished blooming.

  1. Lift the entire plant out of the ground with a shovel.
  2. Divide it in half or more sections using pruners or a spade.
  3. Replant each section in a new location and keep it well-watered until you see new growth in a few weeks.

Self-seeded volunteers can also be dug up and transplanted. Newly germinated seedlings should be planted in early spring.

How to Grow Snow-in-Summer From Seed

Snow-in-summer spreads quickly by reseeding and by producing runners when grown in favorable conditions. Grow snow-in-summer from seed with these simple steps:

  1. Sow the seed directly into your flowerbeds or pots in early spring.
  2. Loosely cover with about 18-inch garden or potting soil.
  3. Water to keep the soil moist but never soggy.
  4. Keep the seeds, if potted, in light so they can germinate.
  5. Look for germination in two to three weeks. Note that new plants won’t bloom until their second year.

Potting and Repotting Snow-in-Summer

Snow-in-summer is a pretty spiller plant for hanging pots. Fill a container of any material with any type of well-draining potting mix. Keep the container in a dry, sunny spot. Make sure the container has plenty of drainage holes. Water this plant infrequently, even in pots. Wrap the pots or put them in a dry, unheated garage during the winter when snow-in-summer is dormant.

Common Plant Diseases

Few if any pests or diseases bother snow-in-summer plants. However, high humidity or too much shade can foster damping-off disease and other fungal problems. Root rot can be a problem in soil that is too moist. Keep your snow-in-summer in a drier area with well-draining soil to avoid these problems.

How to Get Snow-in-Summer to Bloom

Bloom Months

This ground cover’s delicate, woolly, silver leaves spread a mat of evergreen foliage and charming flowers in late spring and early summer (April or May through June, depending on location).

What Do Snow-in-Summer Flowers Look and Smell Like?

Snow-in-summer flowers have five pure white petals and yellow stamens. Flowers can be tiny or slightly larger depending on the type or cultivar. The flowers blanket the ground and have a mild, sweet fragrance.

How to Encourage More Blooms

This ground cover blooms on its own as long as it’s in well-draining soil in a sunny spot. Overwatering may reduce blooms.

Common Problems With Snow-in-Summer

Snow-in-summer is rarely a bother and will grow without much intervention. However, keep an eye out for these signs of potential problems.

Plant Turning Brown

It’s normal for the seedheads of snow-in-summer to turn brown after the flowers fade. If they are browning at the beginning of the season, they may not be getting enough sun or water. Or, the ground may not be draining and the plants are sitting in soggy soil, developing root rot.

Patchy Growth

A carpet of snow-in-summer flowers may look patchy if part of the plantings are overwatered or rotting. Some plants may be older and need replacing after two to three years.

Grows Weedy

Snow-in-summer will grow fast and aggressively in climates that have cooler summers. It’s best to divide weedy snow-in-summer plants to keep them neat. Mow the plants if the patch looks weedy after they bloom.

FAQ

    • Is snow-in-summer an invasive ground cover? Snow-in-summer can grow fairly aggressively or weedy but it is not always considered invasive. However, its cousin, boreal chickweed (Cerastium bieberseiniiCerastium tomentosum L) is listed as an invasive plant in areas around the United States.

    • Do I need to cut back snow-in-summer? You don’t need to cut back snow-in-summer after it flowers but it’s a good idea to do so if you don’t want it to spread or reseed.

    • Is snow-in-summer considered drought-tolerant? Snow-in-summer is considered a drought-tolerant plant and perfect for waterwise gardens.

    • How fast will snow-in-summer spread? One small patch of snow-in-summer can spread as much as 2 to 3 feet in one season.