St. John's Wort
Hypericum cerastoides 'Silvana'

Family: Clusiaceae
Genus: Hypericum (hy-PER-ee-kum) (Info)
Species: cerastoides (ker-ras-TOY-deez) (Info) (ser-as-TOI-deez) (Info)
Cultivar: Silvana

Category:

Alpines and Rock Gardens

Groundcovers

Height:

under 6 in. (15 cm)

Spacing:

6-9 in. (15-22 cm)

Hardiness:

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

Danger:

Unknown - Tell us

Bloom Color:

Bright Yellow

Bloom Time:

Late Spring/Early Summer

Foliage:

Blue-Green

Other details:

Average Water Needs; Water regularly; do not overwater

Requires consistently moist soil; do not let dry out between waterings

Soil pH requirements:

5.6 to 6.0 (acidic)

6.1 to 6.5 (mildly acidic)

6.6 to 7.5 (neutral)

Patent Information:

Unknown - Tell us

Propagation Methods:

From seed; sow indoors before last frost

Seed Collecting:

Unknown - Tell us

Regional

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

Christiana, Tennessee

Gardeners' Notes:

1
positive
0
neutrals
0
negatives
RatingContent
Positive

On Apr 29, 2011, killdawabbit from Christiana, TN (Zone 6b) wrote:

This is fully hardy here in z6b. (see pic at right)