Hypericum kalmianum 'Gemo' · Hypericaceae

Kalm's St. John's Wort

✅ Pet-friendlyPerennial, remaining green throughout the year.60 to 90 cm

LightFull sun

WaterModerate; allow to dry between waterings.

DifficultyEasy

ColdResists light frosts down to minus 5 degrees Celsius.

Full sunModerate; allow to dry between waterings.EasyResists light frosts down to minus 5 degrees Celsius.

Description & origin

Kalm's St. John's Wort is a compact shrub with vibrant yellow flowers. Ideal for gardens, it is hardy and easy to care for. Its leaves are evergreen, maintaining green throughout the year.

Size

Can reach up to 90 cm in height and width.

Foliage

Evergreen foliage that maintains green color year-round.

Flowering

Blooms in summer with bright yellow flowers.

Detailed care

Light

Prefers full sun for abundant flowering.

Soil

Well-drained and slightly acidic soil is ideal.

Watering

Moderate watering, allowing the soil to dry slightly between waterings.

Temperature

Tolerates cold well but prefers temperate climates.

Fertilising

Fertilize in spring with a balanced fertilizer.

Repotting

Transplant in spring or autumn, avoiding extreme heat periods.

Pruning

Prune in late winter to maintain shape and encourage growth.

Propagation

Propagate by semi-hardwood cuttings in summer.

Common problems

Powdery mildew

Can occur in high humidity conditions. Treat with appropriate fungicide.

Leaf spots

Caused by fungi, can be treated with fungicides.

Root rot

Occurs in poorly drained soils. Improve soil drainage.

Uses & curiosities

In the garden

Attracts pollinators
Cold resistant
Ideal for borders

Other uses

Excellent for low-maintenance gardens.

Did you know…

This plant is known for its cold resistance and ability to attract pollinators.