Hypericum dubium
Hypericum dubium · Hypericaceae
The gardener's calendar
Ideal time to plant hypericum dubium: set it out when the soil is neither frozen nor waterlogged, and water generously as it establishes.
ID card
- Foliage
- Deciduous
- Flowering
- June to August, yellow flowers
- Adult size
- 30 to 60 cm in height
- Growth
- Moderate
- Hardiness
- Very hardy, down to -15°C
- Origin
- Central and southern Europe
- Soil type
- Well-drained, tolerates poor soils
Care
Watering
Water moderately during the growing season, once to twice a week depending on conditions. In summer, keep the soil slightly moist without excess. Reduce watering considerably in autumn and winter. Avoid stagnant water at all costs as it promotes root rot.
Light exposure
Place Hypericum dubium in full sun to partial shade for optimal flowering. At least 4 to 6 hours of direct daily sunlight promotes nice branching and generous flower production. In dense shade, flowering decreases and the plant becomes leggy.
Pruning and cleanup
Perform light cleanup in late winter to remove dead wood and encourage branching. You can partially cut back the clump to maintain a compact form. Remove faded flowers to extend flowering and encourage new blooms.
Soil and drainage
Hypericum dubium prefers light, well-drained soil that is undemanding. It adapts to poor, rocky or sandy soils. Enrich the potting mix with well-decomposed compost when planting. Good drainage is essential: avoid heavy, compacted soils that retain moisture.
Fertilizing
Apply balanced fertilizer in spring when growth resumes. Light fertilization once a month during the growing period is more than sufficient. Reduce applications in late summer to prepare for dormancy.
Diseases and pests
Hypericum dubium is generally robust and rarely troubled by pests. Watch for root rot and fungal issues in case of excess moisture. Ensure good air circulation and avoid foliar watering. Outdoors, aphids may occasionally appear: a water spray is usually enough to eliminate them.
Did you know?
The Hypericum genus has been used since antiquity in traditional herbal medicine. Hypericum dubium, like its relatives in the genus, accumulates natural photosensitizing compounds in its leaves and flowers, which explains why certain St. John's Wort species are recommended in naturopathy for general wellness concerns.
Where to buy it
Plant in spring or early autumn, avoiding spells of intense heat. Pick a plant with healthy foliage and roots that are not exposed. Best time: March, April, May, September.
Add this plant to my garden →Plants from the same family
- Rose of sharonHypericum calycinum
- Tall tutsanHypericum inodorum
- Egyptian Saint John's WortHypericum aegypticum
- Hooker's St. JohnswortHypericum hookerianum
- Moser's St. John's wortHypericum moserianum
- Hypericum dummeriHypericum dummeri
Tips generated and checked by Viridia — adapt them to your local climate.