Hoary Cress
Cardaria draba

Family: Brassicaceae (brass-ih-KAY-see-ee) (Info)
Genus: Cardaria (kar-DAR-ee-uh) (Info)
Species: draba (DRAY-buh) (Info)
Synonym:Lepidium draba

Category:

Perennials

Height:

6-12 in. (15-30 cm)

12-18 in. (30-45 cm)

18-24 in. (45-60 cm)

24-36 in. (60-90 cm)

Spacing:

9-12 in. (22-30 cm)

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)

USDA Zone 9a: to -6.6 C (20 F)

USDA Zone 9b: to -3.8 C (25 F)

Sun Exposure:

Full Sun

Sun to Partial Shade

Danger:

All parts of plant are poisonous if ingested

Bloom Color:

White/Near White

Bloom Time:

Mid Spring

Foliage:

Herbaceous

Velvet/Fuzzy-Textured

Other details:

May be a noxious weed or invasive

Soil pH requirements:

Unknown - Tell us

Patent Information:

Non-patented

Propagation Methods:

Unknown - Tell us

Seed Collecting:

Unknown - Tell us

Regional

This plant has been said to grow in the following regions:

Belfield, North Dakota

Baker City, Oregon

Gardeners' Notes:

0
positives
0
neutrals
2
negatives
RatingContent
Negative

On Oct 8, 2009, MaryE from Baker City, OR (Zone 5b) wrote:

Common names for this plant are Hoary Cress, Pepperwort and Whitetop. It is very invasive and becoming more of a problem every year in my area of eastern Oregon where it grows along roadsides, in pastures, in hayfields, cultivated fields, and in everyone's gardens. My weed book (from Idaho) lists it as a noxious weed, and states that it first appeared in North America in the late 19th century along both the east and west seacoasts, apparently having traveled in ships ballast, which included soil as well as rocks. The origin appeared to be Europe.

It spreads by seeds and roots and is a very agressive plant.

Negative

On Apr 1, 2007, Joan from Belfield, ND (Zone 4a) wrote:

This plant is listed on the North Dakota invasive/troublesome list and this information is being distributed in a guide developed by the ND Weed Control Association and other agencies.

Plant Features
Perennial, up to 2.5 feet tall
Leaves clasp stem and are covered with hairs giving plant a grayish appearance
Each stem produces manyflowering branches; creates a white-top appearance
Flowers abundant, 1/4 inch wide, 4 petals
Blooms May through June
Spreads by seeds (July) and deep, creeping roots (rhizomatous)
Egg-shaped seeds
Creates monocultures

Distribution
Documented in a few areas. Grows under most conditions

Interesting Facts
Member of the mustard fami... read more