Growing guide

How to grow penstemons

These elegant easy-to-grow border plants send up spires of tubular flowers in a range of gorgeous colours. From sky blue to rich plum, deep purple to powdery pink, they flower across the summer months, and like a warm, sunny spot.

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Quick facts

  • Easy to grow
  • Flowers from summer through to late autumn
  • Best planted from March to mid-May
  • Penstemons thrive in a sunny position
  • Cut all stems down to low-growing shoots in mid to late March
  • Water in very dry spells
  • Propagate by making cuttings in summer or early autumn

All you need to know

While we think all this information will be helpful to you, we always recommend to read the instruction labels on your plants.

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The Royal Horticultural Society is the UK’s leading gardening charity. We aim to enrich everyone’s life through plants, and make the UK a greener and more beautiful place.