One of the mainstays of high summer, black-eyed Susan or Rudbeckia hirta always performs with one of the longest displays of bloom of any summer bedding plant, whatever the weather. In reality a biennial or short-lived perennial, in the UK we grow it as a half-hardy annual, planted out from late May.
It’s easy to grow rudbeckia from seed, but if you don’t have the facilities it can also be purchased online as a plug plant or from garden centres in full flower, but you won’t always be able to get the variety and colour you want. And it’s depth of colour they have in abundance. These exotic looking daisies on branching plants come in shades of bronze, orange and yellow and even sultry red in the case of variety ‘Cherry Brandy’, along with single to fully double flowers. Single or semi-double bloomers have a distinctive central cone, usually dark and sultry, but, in the case of ‘Irish Eyes’ and ‘Prairie Sun’, a delightful and eye-catching lime green. Growing to around 45-60cm (18-24in)they are ideal for filling borders in a sunny or semi-shaded position, in well-drained soil, tolerating drought once established.
They also perform with great aplomb in pots and window boxes. Once flowering is under way, remove spent blooms to keep them looking neat, and encourage more blooms to form among the coarse, bristly foliage. Seeds can be sown from early April until May indoors or under glass, producing larger plants more likely to bloom than if sown directly outdoors from mid-late May, depending on late frost. Seeds need light to germinate so only lightly cover them with sieved compost of vermiculite, germinating at a temperature of 18-20C (64-68F). Prick out and grow on in modules or 7.5cm (3in) pots, hardening them off for a couple of weeks before planting outside from mid-late May.
Our pick of best rudbeckia varieties
Cherokee Sunset
Double bloomed mixture in orange, yellow and bronze tones. H: 51cm (20in) S: 30cm (12in). From: www.plantsofdistinction.co.uk tel: 01449 721720
Cherry Brandy
First red flowered variety bred by Thompson and Morgan. H:60cm (24in) S:40cm (16in).
From: www.thompson-morgan.com tel:0333 400 0033
Kelvedon Star/Sputnik
Free-flowering, bushy variety. Very weather resistant. H:70cm (28in) S:40cm (16in).
From: www.kingsseeds.com tel: 01376 570000
Prairie Sun
Award-winning variety with two-tone yellow blooms. H:80cm (30in) S: 30cm (12in)From
Grow rudbeckia from seed - step by step
1 Sow in trays in April and May and lightly cover
2 Prick out into modules or 7.5cm (3in) pots.
3 Plant out in drifts in full sun from late May.