Rudbeckias, also known as black-eyed Susan, are much loved for their exuberant flowers that bring a bold splash of colour to the garden from August to October.
The most common rudbeckias, variants of Rudbeckia fulgida, are perennial, with mostly bright yellow petals and a distinctive dark central cone. They range in height from around 60cm to 2m tall, depending on the variety. Rudbeckias derived from Rudbeckia hirta often have have russet, dark-red or brown flowers and are shorter. They are usually grown as half-hardy annuals from seed, but will survive mild winters, flowering in their second and even third year.
Rudbeckias are particularly well suited to prairie-style and naturalistic plantings, alongside other plants that peak in late summer and autumn, such as echinacea, persicaria, asters and ornamental grasses. They also make excellent cut flowers.
Jump to
How to grow rudbeckia
Where to grow rudbeckia
Rudbeckias do best in full sun or dappled shade, but will not do well in poor or very dry soils. Grow them with other tall, upright perennials so that they are naturally supported by them.
When to sow rudbeckia
Rudbeckia hirta cultivars can be raised as half-hardy annuals, sown under glass in late March or early April and planted out in their final positions in late May/early June. They can also be sown direct in their flowering positions in spring. Perennial rudbeckias can be sown in spring, although germination may be erratic.
When to cut back rudbeckia
Rudbeckia fulgida cultivars have attractive seedheads, so can be left standing in the garden over winter, then cut back in February. Otherwise, cut down after flowering in autumn.
Rudbeckia problems
The main problem with rudbeckias is slugs grazing on the young growth in spring, so be vigilant and protect plants if necessary.
More on growing late summer perennials:
The best small-flowered asters to grow
The best rudbeckia to grow
Rudbeckia fulgida var. sullivantii 'Goldsturm'
Widely available, reliable and floriferous. It has dark green foliage and rich yellow flowers. Later in the season it has attractive black pincushion heads and a good winter silhouette. Height: 60cm.
Rudbeckia fulgida var. deamii
More open branched than 'Goldsturm', with rough hairy stems, greyish-green hairy leaves and clear yellow petals. A tough plant that puts up with drier conditions than other Rudbeckia fulgida forms, and possibly more slug resistant. Height: 60cm
Rudbeckia nitida 'Herbstonne'
Rudbeckia triloba
Has the smallest blooms of all the rudbeckias, around 5cm diameter. It is very floriferous, with very dark cones. It suits a position on the edge of woodland. It is a relatively shortlived perennial. Height: 1m.
Rudbeckia triloba 'Prairie Glow'
Masses of small, russet-coloured flowers, with yellow tips, on tall, airy stems. A shortlived perennial. Height: 1.2m.
Rudbeckia hirta 'Cappuccino'
An attractive annual that has burnished orange petals with dark brown markings. Makes a great cut flower. Height: 60cm.
Rudbeckia hirta 'Prairie Sun'
Masses of cheerful yellow flowers with a pale green centre. The petals are two toned, darker yellow near the centre. Looks great in the border or in a vase. Height: 80cm.
Rudbeckia hirta Cherokee Sunset
A beautiful rudbeckia in stunning sunset shades and a dark centre. Makes an excellent cut flower. Height: 60cm.
Here's more summer flowers to grow