St. John's Wort (Shrub)

Use this shrub at the front or middle of a mixed border, leaving taller shrubs and perennials behind it so the summer flowers remain visible. A repeated row can make a low informal edge along a drive, open lawn, or wide path; keep the planting bed deep enough that its rounded form does not spill into circulation space. It also works in grouped native plantings and on slopes or banks where a compact woody layer is useful.^[1][2]

Plant on 3-foot centers for a continuous, shoulder-to-shoulder grouping at maturity. Its mature width is also about 3 feet, so this spacing leaves little open ground between established plants; pull centers farther apart if you want distinct mounds or room for lower perennials between them. Set the front row back from paths by at least half its width, about 18 inches, to preserve clear passage.

Give it full sun for the strongest flowering display, with moderate water while it establishes. It tolerates poor, dry soil and drought, making it a practical choice for sunny sites that are not irrigated regularly. Avoid placing it in a tight, heavily shaded bed where nearby shrubs will crowd its compact form and reduce its light.

The bright yellow flowers occupy the shrub from early summer into late summer, so use it where a long summer accent is wanted after spring bloomers fade. Flowers are produced on new growth; an early-spring pruning window allows the plant to be tidied before the new season begins. Seed capsules can remain into winter, adding off-season structure to a border.^[1][2]