Border penstemons
The bright blooms of border penstemons make a colourful splash througout summer, writes Emma Crawforth
These bright, foxglove-like flowers hail from North and Central America, where around 250 species grow in a range of habitats. The border penstemons have been bred for their large and impressive flowers in a range of jewel-like colours, from pinks through purples to blues, as well as whites and rich reds, occasionally bearing striking markings. With deadheading, some varieties will flower into November.
WHERE TO PLANT
Plant into fertile, free-draining soil in full sun or partial shade. Avoid windy spots and beds that are wet in winter. Penstemons mix well with hardy perennials, grasses and small shrubs.
HOW TO PLANT
Ensure soil is free-draining by forking in organic matter such as well-rotted homemade compost then plant at the same level as in the pots before.
HOW TO PROPAGATE
Sow seed in late winter or spring, germinating at around 15ºC. Alternatively divide a clump in mid to late spring.
PROBLEMS
Slugs and snails can damage penstemons, so use traps to control populations if heavy. Powdery mildew may strike in late summer, especially when the plants are crowded and soil dry. Water in very dry weather to avoid this, aiming at the soil and not splashing the plants.
HOW TO CARE FOR
Protect from cold with a dry organic mulch on the soil in winter, especially in frost-prone areas. Deadhead the flowers but avoid cutting low until early spring.