Hypericum kalmianum
TAXONOMY
FamilyHypericaceae
GenusHypericum
Zone4
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Hypericum kalmianum, commonly known as Kalm's St. John's Wort, is a deciduous shrub native to the Great Lakes region of North America. It is known for its bright yellow flowers that bloom in mid-summer. The plant typically grows to about 3 feet in height and has a rounded form. It is well-suited to rocky or sandy soils and is often found in open woods and along shorelines. The plant undergoes a dormancy period during the winter months.
ALSO KNOWN AS
Kalm's St. John's Wort
Norysca Kalmiana
Hypericum kalmianum var. elongatum
Hypericum lanatum
OVERVIEW
VPDCalculate
WaterDry
SoilLoamy
LightDirect Bright (6 Hours)
Temperature20° C
Humidity50%
Dormancy3 Months
pH6.5
Pressure1,013 mbar
DETAILS
Care Instructions
Kalm's St. John's Wort is relatively easy to care for. It prefers full sun to partial shade and should be watered when the soil is dry. The plant thrives in moderate temperatures and average humidity levels. It is quite hardy and can tolerate a range of conditions, making it suitable for outdoor gardens.Soil
This plant prefers well-drained loamy soil but can tolerate sandy or rocky soils. Good drainage is essential to prevent root rot. The soil should be allowed to dry out between waterings to mimic its natural habitat.Fertilizer
A balanced fertilizer with an N-P-K ratio of 10-10-10 can be applied in the spring to promote healthy growth. Fertilize sparingly, as the plant does not require a high nutrient concentration.Repotting
If grown in a container, repotting should be done every 2-3 years in the spring. Choose a pot that is slightly larger than the current one and ensure it has good drainage. Gently remove the plant from its old pot, shake off excess soil, and place it in the new pot with fresh soil.Propagation
Propagation can be done through seeds or cuttings. For cuttings, take a 4-6 inch stem cutting in late spring or early summer. Remove the lower leaves and plant the cutting in a pot with well-draining soil. Keep the soil moist and place the pot in a bright, indirect light location until roots develop.Pruning
Pruning is recommended to maintain the shape and health of the plant. Prune in late winter or early spring before new growth begins. Remove any dead or damaged branches and trim back to shape the plant as desired.Toxicity
Hypericum kalmianum is not known to be toxic to pets or humans. However, as with all plants, it is best to prevent pets and children from ingesting any part of the plant.Additional
Kalm's St. John's Wort is a great addition to rock gardens, borders, and naturalized areas. It is also known for its medicinal properties, although it is not as commonly used as other Hypericum species. The plant is drought-tolerant once established and can attract pollinators such as bees and butterflies.REVOLUTIONIZE YOUR PLANT CARE
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