Cerastium Species, Mouse-Ear Chickweed, Snow-in-Summer

Cerastium tomentosum

Family: Caryophyllaceae (kar-ree-oh-fil-AY-see-ee) (Info)
Genus: Cerastium (ker-RAS-tee-um) (Info)
Species: tomentosum (toh-men-TOH-sum) (Info)
View this plant in a garden


Alpines and Rock Gardens



Water Requirements:

Average Water Needs; Water regularly; do not overwater

Sun Exposure:

Full Sun



Foliage Color:



under 6 in. (15 cm)


6-9 in. (15-22 cm)

9-12 in. (22-30 cm)


USDA Zone 2a: to -45.5 C (-50 F)

USDA Zone 2b: to -42.7 C (-45 F)

USDA Zone 3a: to -39.9 C (-40 F)

USDA Zone 3b: to -37.2 C (-35 F)

USDA Zone 4a: to -34.4 C (-30 F)

USDA Zone 4b: to -31.6 C (-25 F)

USDA Zone 5a: to -28.8 C (-20 F)

USDA Zone 5b: to -26.1 C (-15 F)

USDA Zone 6a: to -23.3 C (-10 F)

USDA Zone 6b: to -20.5 C (-5 F)

USDA Zone 7a: to -17.7 C (0 F)

USDA Zone 7b: to -14.9 C (5 F)

Where to Grow:

Grow outdoors year-round in hardiness zone



Bloom Color:

White/Near White

Bloom Characteristics:

Unknown - Tell us

Bloom Size:

Unknown - Tell us

Bloom Time:

Late Spring/Early Summer

Other details:

May be a noxious weed or invasive

Soil pH requirements:

6.1 to 6.5 (mildly acidic)

6.6 to 7.5 (neutral)

7.6 to 7.8 (mildly alkaline)

Patent Information:


Propagation Methods:

By dividing the rootball

From seed; direct sow outdoors in fall

From seed; winter sow in vented containers, coldframe or unheated greenhouse

From seed; sow indoors before last frost

From seed; direct sow after last frost

Seed Collecting:

Allow seedheads to dry on plants; remove and collect seeds


This plant is said to grow outdoors in the following regions:

Seward, Alaska

Sitka, Alaska

Flagstaff, Arizona

Belvedere Tiburon, California

Clovis, California

Fairfield, California

Martinez, California

Menifee, California

Penn Valley, California

San Jose, California

Waterbury, Connecticut

Wilmington, Delaware

Idaho Falls, Idaho

Irwin, Idaho

Rathdrum, Idaho

Chadwick, Illinois

Mount Prospect, Illinois

Saint Charles, Illinois

Greenville, Indiana

Louisville, Kentucky

Westbrook, Maine

Elkton, Maryland

Chicopee, Massachusetts

Norton, Massachusetts

Pepperell, Massachusetts

Bellaire, Michigan

Grand Haven, Michigan

Minneapolis, Minnesota

Montevideo, Minnesota

Florence, Mississippi

Marietta, Mississippi

Marshfield, Missouri

Fort Benton, Montana

Dayton, Nevada

Elko, Nevada

Las Vegas, Nevada

Berlin, New Hampshire

Epsom, New Hampshire

Cato, New York

Jefferson, New York

Port Washington, New York

Staten Island, New York

Cincinnati, Ohio

Columbus, Ohio

Haviland, Ohio

Oklahoma City, Oklahoma

Mallorytown, Ontario

Baker City, Oregon

Klamath Falls, Oregon

Portland, Oregon

Jessup, Pennsylvania

Lewisburg, Pennsylvania

Milford, Pennsylvania

Norristown, Pennsylvania

Philadelphia, Pennsylvania

Pittsburgh, Pennsylvania

Clarksville, Tennessee

Knoxville, Tennessee

Lawrenceburg, Tennessee

Unicoi, Tennessee

Hereford, Texas

Farmington, Utah

South Jordan, Utah

Brewster, Washington

Buckley, Washington

CHIMACUM, Washington

MOXEE, Washington

Poulsbo, Washington

Spokane, Washington(2 reports)

Delavan, Wisconsin

Madison, Wisconsin

show all

Gardeners' Notes:


On Apr 22, 2018, Kev81 from Melbourne,
Australia wrote:

We live in Australia and this plant is a great addition. It looks amazing all year round. In spring when its completely covered in those tiny white flowers. But it looks great even when its not in flower with its grey soft foliage. We propagate ours very easily by cuttings. We made a little video [HYPERLINK@youtu.be] Only took a month for the cuttings to be ready for the garden.


On May 26, 2016, NaturallyNikki from Dayton, NV wrote:

I Live outside of Carson City NV. Desert living is VERY different from my No. CA Mountain living, and learning to grow in it has it's own learning curve :-) For one, we have daily winds of 15 mph. It doesn't sound like much unless you live in it.

I try VERY hard to do all my plants by seeds, where at all possible. When I first moved here there was no Spring, really? Okay?...Just snow on the ground. That was in 2002...

...Now it is 2016 and I've got this down pat =) The first ground cover I grew from seed was the 'Snow 'n Summer'. She is a slow grower the first year, but after that, look out! Flowers everywhere and they spread from the 6" dia. plant to 12" in one month (that was in March). I have them growing in terra cotta planters on my deck and ste... read more


On May 15, 2013, sladeofsky from Louisville, KY (Zone 6b) wrote:

I have read very conflicting reports about this plant's ability to withstand heat an humidity. This is my second year growing it and so far it is doing well and trust me, it is very hot and humid here in Kentucky.


On Jun 26, 2012, Clary from Lewisburg, PA (Zone 6b) wrote:

The silvery wooly leaves and tremendous resilience of this plant are wonderful. I started a patch from seed and have since divided it all around the garden. I have not found it to be invasive at all.


On Jun 25, 2012, TiaLee1 from Rathdrum, ID (Zone 5b) wrote:

This plant is tough as nails and gorgeous. The largest mat of it is growing under an old crab apple in the center of a raised and sloping bed that seems to consist of gravel, sand and bark. (former owner) This bed gets plenty of water, due to other species there that need it. I have transplanted some to the front border, where it is in full sun all day and is quite dry. Seems to love it there, as well.

Can't say enough good things about this plant. It is often windy and dry here (zone 5) in summer and wet and cold/frozen in winter. Just a super beautiful, dependable groundcover, sun or shade. (not full shade-dappled morning and afternoon full shade)


On Apr 14, 2012, llittleredhen wrote:

This plant grows well in Merced, CA. Due to the gray appearance of its leave, I am hoping it will be deer resistant in Mariposa, CA. It grows there, but so far the deer have not noticed the small area where it is hidden.


On Oct 12, 2011, fionaly from Worcester,
United Kingdom wrote:

This such a cheerful, pretty trailing/thickly sprawling plant,and so generous in its longevity! Softly tactile, silver grey leaves and the sweetest unpretentious white flowers. It reminds me of my childhood (in north-western England) it grew on a low, wide stone-topped wall, which divided our little front garden from our neighbours'; it seemed to be flowering for months and months on end, and it never actually died! We used to call it 'White Rock'. My father still has some, grown from the original stock, in his border, which is very dry due to several evergreens and hardy shrubs. Last time I visited I took a small rooted sample back to the West Midlands (UK); even though I don't actually have a garden, I have a number of pots around our doorsteps. It's doing quite nicely in a 4'' terraco... read more


On Mar 16, 2010, lehua_mc from Portland, OR (Zone 8b) wrote:

Absolutely a no-fail ground cover, which is to say treat it like a ground cover, not a garden plant. I started mine by seed indoors last spring (why not?), and set out a couple starts. They filled in a hot dry corner that summer in no time, and now a year later have disregarded an 8" gravel edge to start mingling with the grass. It stayed a lovely ever grayish pale green throughout the winter, and for that I've decided this is another great tool for all those hard to deal with areas where I need to keep the weeds to a minimum, can't put a "garden plant", but don't want grass.


On Nov 8, 2009, stormyla from Norristown, PA (Zone 6b) wrote:

This plant grows well is dry windy spots where others fail. It blooms reliably and spreads slowly.


On May 15, 2007, saladgirl from Las Vegas, NV (Zone 9a) wrote:

Las Vegas, NV
This plant does well in spite of our summer heat, providing it receives regular (daily in summer) watering and shade in the mid- and late-afternoon. Surprisingly, it has survived year after year.


On May 22, 2006, zillabug from Cato, NY wrote:

We have had this plant covering a small hillside that nothing else would grow in, and it's proven to be the right plant for the job. During heavy winters (170" snow or more) it has a tendency to thin out, however, it's a prolific re-seeder, and bounces back quite nicely. There are two cultivers that I know of. The more aggresive variety has larger leaves (1 1/2") and has a 'looser', more relaxed look, and covers quickly. The other strain has 1" leaves, and grows slow and tight. This is a handy little plant, but it will need more water in dry, west side plantings verses east side plantings. We have much better luck with the larger leaf variety.


On May 1, 2006, reneesue57 from Oscoda, MI wrote:

Upon moving into our recently renovated 1920's home in Oscoda MI, we needed to plant something that would grow without much fuss on the outside of our fence, between fence and sidewalk. We planted Snow-in-Summer & Russian Sage, alternating three SIS in downward "V" and three RS in upward "V". The result was AMAZING! Beautiful mounds of SNOW half the summer and sprays of lavender sage the other half. It was such a pleasant surprise the first year but when they all came back by themselves without much tending the second year and gave an even MORE spectacular show...well, we were thrilled! The only warning I would give new owners of SIS is to remove any leaves, etc. from atop the green as soon as the snow melts. The leaves will kill the plants quickly.


On Jan 25, 2006, Gabrielle from (Zone 5a) wrote:

I love Snow-In-Summer for a contrast plant; it looks so nice next to a red or purple leaved plant. Light aids germination of seeds.

Blooms mid May to mid June in my garden.


On Feb 4, 2005, MaryE from Baker City, OR (Zone 5b) wrote:

My single plant has grown to a mat of 25x35 inches, in full sun in a hot dry climate with regular watering. It might have done better if it had more shade since my sun is very intense. I'm thinking of moving it since I want to get another plant or two so I can put a small childs sled in the patch to make it look even more like snow in summer. When I get that set up I will take a picture and post it here.


On Nov 13, 2004, 433kfj from klamath falls, OR (Zone 6a) wrote:

I have a large mound of this growing under a pine tree on a slope in front of my house. It's a pretty shady location, but it blooms OK. The problem is that it isn't spreading out, but mounding up. Pine-needles are falling on it and making it like a big mulch pile. I thought I might trim it down lower but I'm afraid the roots might be growing higher in the mound and the original roots below have died out, as it seems to be pretty shallow rooted. This is an old house that I'm renting so I have no idea how long it has been growing there. I'm free to do most any thing I want with the landscape (or what little of it there is!). I'd like to keep it growing, but I think part of the pile might be an ant hill, as there are lots of red ants on this tree ( thank god we don't have fire ants or I'd be ... read more


On Aug 13, 2004, pokerboy from Canberra,
Australia (Zone 8b) wrote:

A tough plant, snow in summers gives a great low water grey carpet in cooler zones. Will not tolerate excessive heat or humidity. Its small single white flowers virtually cover the entire plant in summer resembling snow on the mat of foliage. Good border plant. Grow in full sun. pokerboy.


On Jun 9, 2004, WeedPuhler from Edmonton, Canada,

An old perennial favorite, they are the silver-gray back drop to my Tiger and Asiatic lilies and bulbs. It comes back from slumber ready to bloom its head off... We found this groundcover in some neglected beds in our 30 year old garden, it seems that it likes our brutal Edmonton, Alberta (Canada) winters. I grow it on the edges of my raised planters and it tends to make its way to the centre, yet the shallow roots are easy to pull out, and everyone likes getting them! It approves of bone meal, transplants beautifully and is quite forgiving, as long as it has full sun. I mulch it with fresh peat moss in spring, and it makes them grow taller and softer.


On Sep 15, 2003, imshl12 from Epsom, NH wrote:

This is an awesome plant for those who are not limited by space! Here in New Hampshire USA, I have never watered it, and it grows in both fertile and non-fertile soil! Here is a beautiful accidental combination I ended up with: In a hurry to plant the pieces of the plant that were given to me I quickly threw them into a bed in which I had planted some tulips in late fall. In the spring, I had these beautiful tall white lily flowering tulips above a dense carpet of white cerastium! Breathtaking! The foliage is great for a moon garden as it is silver and glows in the twilight! No care except occasional weeding as it does form a dense mat and even spreads into the lawn a bit which I love! You can mow right over it!


On Aug 8, 2001, killerdaisy from Dallas, TX (Zone 8a) wrote:

Snow-In-Summer is mat-forming, and is known for it's profuse blooming in late spring/early summer. Dainty, white flowers, with wooly, white leaves. Plants spread to about 24", making it the perfect groundcover. It does not tolerant heat nor humidity, and can become invasive in fertile soil. Divide in spring or fall, every two years.