Quick Guide: summer, hardy, sun, height: 45cm/18in, width: 23cm/9in

A native of California, Mentzelia lindleyi is distinguished by stunning, bright yellow flowers 5cm/2in wide with glossy heart shaped petals. Numerous fine gold stamens cluster in the centre of each flower. Lightly scented, mentzelias make a vivid splash of colour in the summer border. They are also known as Bartonia aurea. No named varieties of the species are available.

PROPAGATION Sow seeds directly in the flowering site in spring and thin the seedlings to 23cm/ 9in apart when they are large enough to handle.

GROWING Mientzelias do best on well-drained fertile soil into which well-rotted organic matter has previously been incorporated.

POSSIBLE PROBLEMS Generally trouble-free.