Naturally found in a wide range of habitats in North and Central America, penstemons produce pretty foxglove-type flowers and sword-shaped leaves from late summer well into the autumn. Happy in most gardens, these long-lasting, hardy perennials loved by pollinating insects are especially suited for the herbaceous border where their colourful and elegant flowers will blend seamlessly, however recently planted. Try mixing with a selection of campanulas, echinaceas, euphorbias, nepetas, rudbeckias and verbenas. Alternatively, weave through soft, flowing grasses.
Plant in deep, fertile well-drained soil in full sun and provide staking if needed. Dead-head regularly to enjoy a continuous display and cut down to ground level after flowering. Divide as needed in spring.
Penstemons are supplied in 9 cm pots. Always unpack and plant on arrival.
Potential problems, pests and diseases:
Penstemons are resistant to rabbits, deers and slugs. However they may be affected by:
- Eelworms: these microscopic pests navigate through plant tissues and feed on cells. Leaves gradually turn yellow, distort and die back prematurely whilst growth may be stunted. Watch out for any signs of infestation and destroy any affected plant at first sight. Dispose of any deceased plant material and debris ahead of the growing season to prevent any risks of infestation.
- Powdery mildews: these fungal diseases usually caused by planting in the shade or by poor air circulation can be seen in the form of white, powdery coating on the leaves. Cut off any infected material before disinfecting your scissors.