How to Plant and Grow Snow-in-Summer

Blankets of sparkling small white blooms from late spring to early summer give this tough perennial groundcover its name. After the blooms fade, the plant's woolly silver foliage remains; it can handle some of the toughest droughts and is hardy in Zones 3-10. However, careful pruning and maintenance are needed to control this invasive plant.

Where to Plant Snow-in-Summer

Snow-in-summer provides a sturdy option for adding botanicals to the cracks of retaining walls and between the stones in a rock garden. Because this plant excels at self-seeding, you're likely to find it in your garden where it's never been planted.

How and When to Plant Snow-in-Summer

Snow-in-summer works in sunny spaces as a ground cover. Use it in rock gardens, as a floral accent to stone walls, or for a fill-in where spring bulbs have stopped blooming. Snow-in-summer prefers mild temperatures and is salt-tolerant, so it's a good plant for seaside locations. Plant snow-in-summer from seedlings in spring.

Snow-in-Summer Care Tips

In a less-than-ideal environment, snow-in-summer can be temperamental. But if its ideal conditions are met, snow-in-summer can become aggressive and invasive.

Light

For the brightest silver foliage, make sure your snow-in-summer gets full sun. Anything less runs the risk of rot, the foliage becomes more gray-green, and the plant gets leggy.

Soil and Water

Because snow-in-summer is native to dry, rocky areas, keep drainage a priority when growing this plant. The plant's roots may rot if the soil stays wet for long periods, and it doesn't do well in rainy places.

Temperature and Humidity

Snow-in-summer doesn't handle high humidity and summer heat well, especially if the plant remains wet. Consider this plant a short-lived perennial or even an annual if you plan on growing it in a warmer climate.

Fertilizer

Because snow-in-summer does well in all types of soil (except very wet soil), it doesn't need fertilizer. If you're not happy with how your plant is performing, you can add a high-phosphorous product, following manufacturer's directions, before the plant blooms to give it a boost.

Pruning

Pruning is crucial to controlling the spread of snow-in-summer. One way to prevent the spread is to remove spent blooms (and any potential seeds) right after the plant flowers. In addition, because snow-in-summer typically finishes flowering all at once, you can trim back the whole plant at one time. Regular trimming also keeps the foliage compact instead of long and leggy. Snow-in-summer spreads by runners, too, so keep them trimmed to prevent unwanted growth.

Pests and Problems

Snow-in-summer's most significant problems are root rot from too-damp soil and fungal diseases caused by too much damp air. Control both of these to minimize issues.

How to Propagate Snow-in-Summer

As this plant ages, it may die out in the middle. Remedy the situation with propagation by digging up the plant, dividing it, and replanting it.

Snow-in-summer can be propagated from seeds. Sow seeds 12 inches apart in early spring on top of garden soil, cover with a sprinkling of soil, and they'll germinate in a few weeks. However, they won't flower for another year.

Types of Snow-in-Summer

'Silver Carpet' Snow-in-Summer

In spring and summer, Cerastium tomentosum has bright silver foliage topped with bright white blooms. Zones 3-7.

Snow-in-Summer Companion Plants

Dianthus

Pinks are treasured for their grasslike blue-green foliage and abundant starry flowers, which are often spicily fragrant. Depending on the type of pink, flowers appear in spring or summer and tend to be pink, red, white, rose, or lavender, but come in nearly all shades except true blue. Plants range from tiny creeping groundcovers to 30-inch-tall cut flowers. Foliage is blue-green. Zones 3-10

Veronica

Easy and undemanding, veronicas catch the eye in sunny gardens over many months. Some have mats with loose clusters of saucer-shaped flowers, while others group their star or tubular flowers into erect tight spikes. A few veronicas bring elusive blue to the garden, but more often, the flowers are purplish or violet blue, rosy pink, or white. Zones 3-11

Yucca

A yucca in bloom produces spires of large, bird-attracting white flowers in summer and fall. The evergreen rosettes of stiff, sharply pointed leaves are often variegated with cream or white. Use them at the end of a walkway, mass them as a barrier, or plant them as accents throughout the border. Site away from paths or other places people could be scratched by their sharp leaves. Zones 3-10