Barbarea, also known as 'wild cress', can be biennials or perennials, with simple or pinnate leaves and small, 4-petalled yellow or white flowers, followed by slender seed-pods
With its silvery-grey, velvetty foliage this is an all year round addition of class to a rockery. The tiny yellow flowers May-September resemble tiny buttons. Height 15 cm. Spread 40 cm
Mostly grown for its lacy silver grey foliage, which will look well in any rockery. The yellow flowers will appear in Spring. Best planted in a sunny spot. Height 15 cm. Spread 20 cm.
A compact grower, dark green foliage showing all year. Its bright golden yellow flowerspikes are set well above foliage and carry a spicy scent all summer. Height 25 cm. Spread 20 cm.
An evergreen addition for the rockery, front of border or walls. Single yellow flowers with orange eye against silver-green foliage in early summer. Second flush in late summer. Height 20 cm. Spread 40 cm.
If you want to add a touch of grey to your rockery this is a good choice. The pale yellow flowers have darker yellow centres and appear from Spring. Height 20 cm. Spread 40 cm.