Oysterleaf

Mertensia maritima

Native to:
Canada, Denmark, Finland, Føroyar, Greenland, Iceland, Ireland, Kuril Is., Labrador, Norway, Russia, Svalbard, Sweden, United States

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Boraginaceae
Genus:
Mertensia
Species:
Mertensia maritima
USDA Symbol:
MEMA3

Growth Characteristics

Life Cycle:
Perennial
Growth Habit:
Forb/herb
Height:
60 cm
Light Requirements:
Full Sun
Drought Tolerance:
Medium
Bloom Months:
may,jun,jul,aug
Bloom Colors:
blue, pink
Ground Cover:
Yes

Wildlife Benefits

Bees:
★☆☆☆☆ Documented bee visitation (GBIF)
Butterflies & Moths:
★☆☆☆☆ Documented Lepidoptera association (GBIF)
Caterpillars:
★☆☆☆☆ Recorded caterpillar host plant (HOSTS Database)

Keystone Species Ranking

Caterpillar Keystone:
★☆☆☆☆ Butterfly & moth species supported by this genus (NWF)

Host Plant for Caterpillars

Udea itysalis

Garden & Ecology Notes

Wildlife Value:
bees, butterflies
Deer Resistant:
Yes
Salt Tolerant:
Yes

Soil Requirements

Soil Type:
sandy, well-drained, nutrient-poor soil
pH:
6.0 - 7.5 (slightly acidic to neutral)
Drainage:
excellent drainage required
Moisture:
dry to moderate
Notes:
native to coastal areas with salty conditions

Propagation & Germination

Stratification:
Cold/moist stratification required — 30–90 days
Germination Time:
14–60 days
Notes:
Seeds require cold stratification and may have erratic germination. Fresh seed germinates best.

The above propagation data sourced from Claude AI

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

Source: Claude AI

ORGHPS Germination Guide: Sow @ 4C for 3 weeks, then place @ 20C.

Source: Ontario Rock Garden & Hardy Plant Society