Frequently asked questions
How do I care for my penstemons?
THE best time to plant penstemons is during spring or summer when the soil has warmed up and their roots should have filled at least the size of a 3.5in (9cm) pot. Choose an open, sunny position and in groups, set them 18in (45cm) apart. On my rich clay soil I never feed penstemons, but on poor sandy soils they would benefit from a general fertiliser in spring and a highpotash liquid feed midseason. Deadhead for the best results but leave old stems in place for winter and don’t cut them back until new growth reaches 3in (8cm) long in spring.
Can I take cuttings of penstemons?
PENSTEMONS root readily from slightly riper stems taken in mid to late summer. The plants resent disturbance, so to expand or start a new group, raising new plants from cuttings is the best method. Rooted cuttings are also good insurance against winter losses. Take nonflowering side shoots (or remove flower buds), trim to 3-4in (8-10cm) by cutting under a leaf node, remove lower leaves and cut any larger ones by half. Insert five into a 3.5in (9cm) pot of 50:50 multipurpose compost and grit, water in and cover with a lid, or ventilated polythene bag, and place out of full sun to root.
Can I grow penstemons from seed?
PLANTS usually bloom in the same year from seed sown thinly and evenly into a pot or tray in spring. Place seeds in gentle warmth around 60-65°F (1518°C) and they should germinate within three weeks. Transplant seedlings singly to 3.5in (9cm) pots and grow on ready for planting out. P. ‘Sensation Mixed’ delivers a wide range of colours at 2ft (24in) high or for smaller flowers in pink, purple and rose, choose P. ‘Miniature Bells’. From unusual P. digitalis ‘Mystica’ expect bronze leaves followed by stems of lavender-pink flowers.