Hypericum dummeri
Hypericum dummeri · Hypericaceae
⚠️ Millepertuis : contact cutané peut causer photosensibilité et dermatites. Ingestion entraîne troubles gastro-intestinaux chez chats, chiens, humains.
The gardener's calendar
Hypericum dummeri is in full bloom: enjoy it, watch watering in hot weather and let spent flowers feed pollinators before pruning.
ID card
- Scientific name
- Hypericum dummeri
- Family
- Hypericaceae
- Type
- Herbaceous shrub
- Adult height
- Approximately 120 cm
- Flowering
- July to September
- Flowers
- Bright yellow
- Foliage
- Deciduous
- Hardiness
- Good (temperate zones)
✓ Taxonomy verifiedSource: AI estimate · hardiness: reliability medium.
Expert tips
The key tip
Less demanding than H. hookerianum but same principle: keep a compact shape with light summer pruning after flowering.
The common mistake
Neglecting pruning and letting the plant stretch out and produce few flowers; it becomes ungrateful quickly if left to its own devices.
The pro's trick
Work in fine gravel at planting time; H.
Care
Sunlight
St. John's wort shrub appreciates full sun for generous and prolonged flowering. It tolerates light partial shade, but may become leggy and flower less abundantly. Place it in a well-exposed location, sheltered from strong winds if possible.
Watering
Water moderately, keeping the soil moist without saturating it. Let the soil surface dry slightly between waterings. Once established, this shrub shows good drought tolerance; increase watering during hot periods and in case of persistent dryness.
Soil and planting
St. John's wort shrub adapts to most soils, provided they are well-drained. Avoid overly wet or marshy ground. Adding well-decomposed compost at planting time will promote establishment; neutral to slightly acidic soil is ideal.
Fertilizer
A balanced fertilizer application in spring is generally sufficient. Avoid overdosing nitrogen, which would encourage foliage at the expense of flowering. You can reapply in early summer to support flower production.
Pruning and maintenance
Prune lightly in late winter or early spring to maintain a compact shape and encourage branching. Remove dead or damaged stems. After flowering, gentle deadheading prolongs the flowering period and improves the plant's appearance.
Diseases and pests
St. John's wort is generally robust against pests and diseases. Excess humidity can promote powdery mildew or rot; ensure good air circulation around the plant. Occasionally inspect the leaves for any signs of abnormality.
Did you know?
The Hypericum genus has been used since antiquity in traditional herbalism, notably in Europe where St. John's wort was associated with protective virtues during St. John's Day ceremonies. Though famous for its historical properties, the shrubby St. John's wort truly shines in the garden with its bright yellow flowers that emerge late in the season, brightening borders when many other plants are fading.
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
- Kalm's St. John's-wortHypericum kalmianum
Tips generated and checked by Viridia — adapt them to your local climate.