With Rhododendron cat. 'Boursault', you get a classic, cold-hardy rhododendron that brings big spring color and year-round structure. This broadleaf evergreen shrub forms a dense, mounded plant with leathery green foliage and large trusses of lilac-purple to purple-pink flowers that light up the garden in late spring.
Plant it where you can give it moist, well-drained, humus-rich soil and consistent moisture. Like most rhododendrons, it performs best in acidic conditions and benefits from a generous layer of organic mulch to keep roots cool and evenly moist. Avoid digging or cultivating deeply around the plant; its roots are shallow and appreciate an undisturbed surface.
Site your shrub in sun to part shade, with shelter from harsh winter wind and the hottest afternoon sun where summers are intense. Water during dry spells, especially in the first few seasons, and remove spent flower trusses after bloom if desired to keep the plant tidy. Prune only lightly and, when needed, prune right after flowering so you do not remove next year's buds.
At maturity it can become a substantial landscape shrub, so allow room for its eventual width and height. Use it as a foundation accent, in woodland borders, or as an evergreen backdrop behind perennials and spring bulbs.