Snow-in-summer

Discuss this plant with the guide — choose this profile as a possible match and prepare your observations for Colorado Plants & Practical Care.

Cerastium tomentosum

Introduced garden groundcover. S12 S11

Spreading habit · Safety gap. Native status, garden use and noxious-weed class are separate from toxicity. Exposure help.

Still researching this plant

This is a sourced working profile. Evidence is incomplete for People, Dogs & cats, Other animals. Independent botanical and veterinary review is pending. Uncertainty is not a finding that the plant is safe.

Three views of this plant

Photos are source-identified examples, not a complete identification key. Check leaves, stems, flowers and fruit together. Locations are not assumed to be in Colorado.

**flower** — Several white flowers with deeply notched petals above gray-green foliage.
Salicyna · CC BY-SA 4.0
Photo source and identification
Original record · Original image
Source-supported identification with visual consistency check Photo selection verifies source labeling and visible consistency; it is not an independent specimen determination.
Downloaded source thumbnail; no further pixel edits. Gallery display preserves the full image; the catalog preview uses a CSS crop.

**flowering stem** — Entire slender flowering stem against the sky, with opposite narrow leaves and a few flowers near its top.
Stefan.lefnaer · CC BY-SA 4.0
Photo source and identification
Original record · Original image
Source-supported identification with visual consistency check Photo selection verifies source labeling and visible consistency; it is not an independent specimen determination.
Downloaded source thumbnail; no further pixel edits. Gallery display preserves the full image; the catalog preview uses a CSS crop.

**leaf and stem** — Source-assembled photographic plate showing narrow hairy leaves in opposite pairs on stems, with a 20 mm scale.
Stefan.lefnaer · CC BY-SA 4.0
Photo source and identification
Original record · Original image
Source-supported identification with visual consistency check Photo selection verifies source labeling and visible consistency; it is not an independent specimen determination.
Downloaded source thumbnail; no further pixel edits. Gallery display preserves the full image; the catalog preview uses a CSS crop.

Recognize

A low mat of woolly, pale foliage and white flowers. Originates in Italy; CSU lists it for hot, dry, sunny groundcover sites. S12 S11

Plants & habitat

Spreads by underground runners and seed. CSU describes it as aggressive; garden judgment: keep it from overtaking smaller neighbors. S11 S12

People

The sources used for this profile do not establish human ingestion safety. S11 S12

Dogs & cats

No species-specific veterinary safety conclusion was established in this review. Do not interpret that gap as pet-safe. S11 S12 S25

Other animals

Flowers attract bees. Safety for grazing animals is not established by the sources reviewed. S12

Before taking action

Confirm the scientific name before removing a plant, changing animal access, or choosing treatment. An evidence gap means this review has not resolved the question. It does not mean safe. For listed weeds, consult your county weed program about the requirements for your location; follow the current label for any pesticide. S27

References

S12 — Cerastium tomentosum, NC State Extension · Plant Toolbox. Accessed 2026-09-07T00:23:54+00:00. Locator: Description; origin; Wildlife Value.
S11 — Ground Cover Plants, Colorado State University Extension. Accessed 2026-09-07T00:23:54+00:00. Locator: Table 1b: hot, dry, sunny exposures; Cerastium tomentosum.
S25 — Toxic and Non-Toxic Plants, ASPCA Poison Control. Accessed 2026-09-07T00:23:56+00:00. Locator: Any plant material may cause vomiting or gastrointestinal upset; database limitations.

Content revised 2026-09-07 02:43:00Z · Source checks dated separately in the references.