For weeks at a time, starting in early spring, its foliage completely disappears under a carpet of small, four-petaled, highly perfumed flowers. Afterward, it makes a very acceptable foliage plant, with dense evergreen growth usually covering the stems almost to their base. They can spread almost without limit under the right conditions. They're not really invasive but bear watching in the rock garden. In perennial borders, taller plants cast some shade to keep these sun-lovers nicely in check.
Poor drainage can be fatal to rock cresses, especially in humid-summer areas.
Try tucking a mulch of fine gravel around the base of the plants and anywhere their stems touch the ground. This helps ensure better drainage and aeration under humid conditions. Rock cresses tend to fall apart after blooming, especially in hot-summer climates, losing most of their leaves to reveal a stringy mass of stems. They will quickly resprout and fill in nicely. In the wild, rock cress grows on rocks and cliffs, so it looks right at home in a rock garden or planted in walls.