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Mount Olympus St. John's Wort

Hypericum olympicum (hy-PER-ih-kum oh-LIM-pi-kum)

Family: Hypericaceae Unknown Groundcover (<1 ft)

Reaching only about 9 inches tall, Mount Olympus St. John's Wort is a perennial subshrub in the Hypericaceae family with showy, yellow flowers and simple broad leaves. Native to the north and central Balkan Peninsula to northwest Turkey, it is relatively rare outside of the alpine environments of Albania, Bulgaria, Greece, Turkey, and Yugoslavia. The plant has an upright or spreading habit, depending on the cultivar, and some cultivars can grow taller. The plant grows well in moist, well-drained soils or many types including clay. Mount Olympus St. John's Wort should be planted in May or June to flower from June to August. Cuttings should be taken from May to July. The plant usually takes 5 to 10 years to reach its full height, but much less than that to reach maturity. Diseases, Insect Pests, and Other Plant Problems: No known diseases or insect pests.

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 54 attributes.

How it fits the guild

Guild layer 5 - Groundcover (<1 ft) Optimal soil pH Acid (<6.0); Alkaline (>8.0); Neutral (6.0-8.0)
See companions & conflicts ↓

Companions & Conflicts

Curated pairwise relationships between this plant and others in the library — who feeds whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.

No curated interactions recorded for this species yet.

Also noted by NC State

Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.

Fills a similar niche Dianthus caryophyllus Euphorbia characias subsp. wulfenii Kalanchoe

Full plant profile

Growing Conditions
Plant type
Perennial; Shrub
Life cycle
Perennial
USDA zones
5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b
Light
Full sun (6 or more hours of direct sunlight a day) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
Clay; Loam (Silt); Sand
Soil pH
Acid (<6.0); Alkaline (>8.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage | Moist
Available space
12 inches-3 feet
Mature size
Height: 0 ft. 4 in. - 0 ft. 9 in. | Width: 0 ft. 4 in. - 1 ft. 8 in.
Growth rate
Slow
Maintenance
Medium
Canopy layer
5 - Groundcover (<1 ft)
Form & Appearance
Habit / form
Dense; Erect
Texture
Medium
Foliage
Broadleaf Evergreen; Deciduous
Leaf color
Gray/Silver; Green
Leaf type
Simple
Leaf arrangement
Opposite
Leaf shape
Elliptical; Lanceolate; Oblong
Leaf margin
Entire
Leaf size
1-3 inches long, < 1 inch wide
Hairs present
No
Leaf detail
Gray-green deciduous leaves, translucent-dotted.
Flower color
Gold/Yellow
Flower value
Good Cut; Showy
Flower form
Cyme
Flower shape
Tubular
Flower size
1-3 inches
Flower detail
Erect stems with large golden yellow flowers. A very showy plant that blooms throughout the summer.
Bloom time
Summer
Fruit color
Blue; Brown/Copper
Fruit type
Capsule
Fruit size
1-3 inches long, < 1 inch wide
Fruit detail
Occasionally berry-like.
Wildlife & Ecology
Native status
Unknown
Origin
Northern and Central Balkan Peninsula to Northwest Turkey
Distribution
United Kingdom
Food & Medicine
Fruit type
Capsule

Edibility

While the species is not harmful to humans, it can be toxic to dogs, cats, and horses, and should be planted away from such animals.

Landscape Use
Landscape location
Container; Patio; Pool/Hardscape; Small Space; Walkways
Landscape theme
English Garden; Rock Garden
Design feature
Border; Small groups
Garden tags
#yellow flowers #dwarf #subshrub #evergreen #showy flowers #perennial #problem for cats
Problems & Resistance
Problems
Problem for Cats; Problem for Dogs; Problem for Horses
Propagation
Seed; Stem Cutting

Planted at Hunnicutt

Nobody’s planted this one yet.