Cut back severely after flowering has finished. Do not prune in fall. Remove damaged stems in spring. 'Silver Carpet' has frosty, white foliage, is compact and less aggressive.

Do you cut back Cerastium?

The plant grows 6 to 8 inches tall with blooms that rise slightly above the mat-forming foliage. ... Annual pruning is important to keep this ground cover plant looking its best.

When should you cut back snow-in-summer?

Pruning. After they have dumped their "snowfall" of white blooms in early summer, trim away the faded blooms and some of the foliage to keep snow-in-summer plants looking attractive for the rest of the summer.