Kalm's St. John's wort

Kalm's St. John's wort (Hypericum kalmianum) should be watered moderately. This species prefers moist soil, so it is important to maintain it with regular watering. During the spring and sunny summer months, water deeply when the soil feels dry to a depth of at least 4 inches. In late summer and fall, reduce the frequency of watering as the soil will stay somewhat wetter. Aim to water once per week during these seasons. During the winter, wait until the top inch of the soil has dried out before providing water to the plants. During extended periods of dryness, it may be necessary to water more frequently.

Kalm's St. John's wort (Hypericum kalmianum) is a native North American plant species that grows best in full sun or partial shade. It should receive at least 6 hours of direct sunlight per day, preferably in the morning or late evening. Plants will suffer if given too much sun, so avoid direct midday sun and instead move to more shaded areas. Planted in areas that are too shady, the plant may not develop its vibrant yellow-green foliage or have fewer flowers.

Kalm's St. John's wort should be pruned in the late winter or early spring, usually any time between February to April. Pruning should be done to promote better circulation of air among the shrub's branches and stimulate healthy flower and leaf growth. This can be done by removing dead, weak, or broken branches and any limbs crisscrossing over each other. Additional pruning can be done to control the size and shape of the plant. Generally, Kalm's St. John's wort does not need to be pruned every year, rather just occasionally to avoid over-pruning.