Kalm's St. Johnswort

Hypericum kalmianum

Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Hypericaceae
Genus:
Hypericum
Species:
Hypericum kalmianum

Growth Characteristics

Life Cycle:
Perennial
Growth Habit:
Shrub
Height:
3-4 ft
Light Requirements:
Full Sun
Drought Tolerance:
High
Bloom Months:
jul, aug
Bloom Colors:
Yellow
Landscaping Shrub:
Yes

Native Range

United States: District of Columbia, Illinois, Indiana, Michigan, New York, Ohio, Wisconsin, Canada: Ontario, Quebec

Keystone Species Ranking

Caterpillar Keystone:
★★★☆☆ Based on number of butterfly and moth species using this genus as host plant (Source: National Wildlife Federation)

Reported Fauna Sightings

Bees: Brown-belted bumble bee (Bombus griseocollis), Brown-belted bumble bee (Bombus griseocollis), Common eastern bumble bee (Bombus impatiens), Common eastern bumble bee (Bombus impatiens), Two-spotted bumble bee (Bombus bimaculatus), Two-spotted bumble bee (Bombus bimaculatus)

Soil Requirements

Soil Type:
sandy, well-drained, nutrient-poor soil
pH:
5.5 - 7.5 (slightly acidic to neutral)
Drainage:
excellent drainage required
Moisture:
dry to moderate
Notes:
Native to rocky, sandy shores and dunes

Germination Information

Pre-treatment: Cold-moist stratification for 30 days at 1–5°C (34–41°F).

Source: OpenAI GPT-4o