Kalm’s St. John’s Wort (Hypericum kalmianum)
Estimated Height at Pickup: 2-3’, 1 gal
A low growing shrub with bright yellow mid-summer flowers! Easy to grow with a naturally round shape, and flowers that fade to a lovely copper as they age. We recommend this species for a smaller, landscaping friendly shrub. (For dense prairie-style plantings, the very similar shrubby St. John’s Wort is slightly larger and less likely to get lost in the wildflowers!) Prefers well drained soils, but is very adaptable as long as it’s not in hardpan clay.
Pollination: Likely self pollinating.
Light: Full Sun, Part Sun/Shade
Soil Moisture: Wet Mesic, Mesic, Dry Mesic
Soil Type: Sandy Loam, Rocky Loam
Height: 1’-3’
Width: 1’-3’
Bloom Color: Yellow
Bloom Time: Jul-Aug
Fruit: Small seed pods contain many small seeds.
Fall Color: Yellow
Root Type: Branching
Notable Wildlife Interactions: Flowers attract bees. Hosts a few moths including the wavy-lined emerald, and a few number of smaller insects. Rarely browsed by mammals.
Notes: Tolerates seasonal flooding, but not standing water. Tolerates some drought once established. If desired, prune after flowering.