Hardiness: 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) USDA Zone 8a: to -12.2 °C (10 °F) USDA Zone 8b: to -9.4 °C (15 °F)
On Feb 10, 2008, Malus2006 from Coon Rapids, MN (Zone 4a) wrote:
I have a small patch that I brought at a plant sale - it multiply slowly and prefer more shade. It is also hard to very hard to find in the plant trade - so far I have only found a few websites that sells it plus C. diphylla - two leaf toothwort. The few other sources where you can buy them are at spring plant sales where the seller are fellow gardeners as they are not viable for non specific nurseries as they tend to disappear when stressed or during the summer, leaving behind a dirt pot. Both are the most commonly sold native cardamine. They are really nice plants, very tame compare to the other members of the mustard family and have interesting flowers if you are willing to look up close to them. There are large patches of it in Coon Rapids Dam park in flat locations but a bit higher up - you can tell where they grow by the large amount of ground plants - very few plants grow where the floods come every five years or so.
On Aug 31, 2001, smiln32 from Oklahoma City, OK (Zone 7a) wrote:
Toothwort (also commonly called cut-leaved toothwort) is a Missouri native spring wildflower which occurs in rich woods and wooded slopes throughout the State and typically grows 8-15" tall. This is a spring ephemeral which blooms in early spring before the leaves emerge on deciduous trees and goes dormant by late spring to early summer. Stems rise directly from rhizomes. Each stem has a whorl of three leaves near the middle of the stem, with each leaf divided into three, narrow, sharply-toothed, lance-shaped segments. A terminal cluster of four-petaled, white flowers (sometimes with a pink blush) blooms at the top of each stem. Flower petals are arranged in the shape of a cross.
This plant has been said to grow in the following regions:
Washington D.c., Louisville, Kentucky Brookeville, Maryland Erie, Michigan Grand Rapids, Michigan Minneapolis, Minnesota Cole Camp, Missouri Glendale, Missouri Elizabeth City, North Carolina Chesterland, Ohio Glouster, Ohio Grove City, Ohio Dickson, Tennessee Viola, Tennessee Leesburg, Virginia