Moderate-growing snow-in-summer makes an excellent ground cover for dry, sunny areas. It is deer resistant and often used in rock gardens or as a cover to fill in after spring bulbs are finished. It also can be used to fill pockets in stone walls. After they have dumped their “snowfall” of white blooms in early summer, trim away the faded blooms and some of the foliage to keep the plants looking attractive for the rest of the summer. Snow-in-summer is grown as much for the glorious silvery carpet of foliage as for their attractive flowers. To avoid rampant spreading, shear the flower stems off before seeds can be dropped. Trimming can be done easily with a lawnmower set high or with a string trimmer. Then, carefully clean up what you’ve cut away to prevent it from reseeding. Some cultivars are more compact and less likely to spread uncontrollably.
Light
This plant prefers full sun conditions. In the shade, snow-in-summer can develop fungal problems. You can avoid this by giving it the light it needs.
Soil
Snow-in-summer thrives in well-draining soil, preferring it slightly acidic (pH 6.0 to 7.0). But 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 is suitable for growing in USDA hardiness zones 3 to 7. This is a plant that likes relatively cool, dry summers. It will be very short-lived if planted in hot, humid climates.
Fertilizer
This plant generally does not need any type of special feeding; it prefers rather poor soils. If you feel your snow-in-summer isn’t performing the way you’d hoped, a fertilizer that’s high in phosphorous, right before your plant blooms, might do the job. For the amount to use, follow the product label instructions.
Varieties of Snow-in-Summer
‘Silver Carpet’: features a more compact flowerhead and is slower spreading’Yo Yo’: produces abundant blooms’Columnae’: boasts features similar to ‘Silver Carpet’ but it is a lower-growing plant, forming 4-inch mounds’Olympia’: grows in clumps 6 to 8 inches tall and up to 18 inches wide with upright flower stalks
Propagating Snow-in-Summer
Snow-in-summer can be divided and replanted to create new plants. Division is best done immediately after the plants have finished blooming. 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
It is also easy to grow snow-in-summer from seed. Simply sow the seed directly into your flowerbeds in early spring, and loosely cover with about 1/8-inch garden or potting soil. Germination should occur in two to three weeks. New plants won’t bloom until their second year.
Common Pests and Diseases
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. Keeping your snow-in-summer in a drier area, with well-draining soil, will solve these problems.
