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No Quibble GuaranteeHow to grow Penstemon
Known as beardtongues for their prominent furry stamens, Penstemon are valuable and hardworking plants for the garden; reliably returning for several years, blooming for months on end and they are amazingly easy to propagate.
The pretty bell-shaped blooms hang from straight sturdy stems, similar to foxgloves and snapdragons in appearance, and are loved by bees.
Penstemon look great when planted in groups of odd numbers and work best in the middle to front of the border where they will grow to an approximate height of 60 cm and spread of between 45-60cm.
Key Information
Soil pH
Position
Hardiness
Where & when to plant Penstemon
The best time of year to plant Penstemon is spring so the roots have plenty of time to develop before their first winter in the ground.
Penstemon thrive in full sun but can tolerate a little shade so consider this along with the eventual height and spread of your chosen variety when choosing a planting site.
How to plant Penstemon
Dig a hole slightly wider and deeper than your plant and add a shovel-full of organic matter - homemade compost or well-rotted cow or horse manure is perfect. A handful of chicken manure pellets will also provide a great slow-release fertiliser to encourage healthy development of young plants.
If drainage on your soil is poor or you are growing in heavy clay, then dig plenty of horticultural grit into the planting hole first.
Gently tease your Penstemon from its pot and carefully loosen its roots before placing in the hole with the crown of the plant just level with the surface of your soil. Fill the edges of the plant with garden soil and firm around the base carefully before watering in.
If you are growing from plugs, then pot the small plants on into pots of multipurpose compost for a few weeks and keep them in a sheltered area before planting out into their final situation. Ensure your plug plants are watered regularly, especially if the weather is warm.
What to plant with Penstemon
Penstemon are available in a glorious range of soft pastel and bright jewel colours and fit well into both contemporary and traditional cottage planting schemes adding a mid-height level to the garden border.
Here are a few of our suggestions for some winning Penstemon planting combinations…
Deep and dramatic Penstemon Plum Jerkin with acid green Alchemilla mollis
Pure white Penstemon Snow Storm with graceful Ammi majus
Pale pink Penstemon Appleblossom with romantic soft garden Roses
Richly coloured Penstemon Garnet with lush green Hosta
Vibrant cerise Penstemon Just Jayne with bright orange Geums
Unusual Penstemon Dakota Burgundy with delicate Anthriscus Sylvestris Ravenswing
Please contact our lovely Customer Care Team at Hayloft if you would like any more help or specialist planting advice for your Penstemon.
How to care for Penstemon
Penstemons are short-lived perennials – they will return for the first few years growing stronger each season but may start to lose vigour after several years. Many gardeners choose to take cuttings regularly to keep up a good stock of these wonderful plants.
A balanced fertiliser such as liquid seaweed feed or growmore should be applied to Penstemons in spring with a layer of mulch to ensure a long blooming season.
In autumn, the plants can be cut back by a third which should encourage a second flush of flowers. You should leave the faded foliage on your plants over winter as they will provide protection to the emerging buds in early spring. The dead stems can be pruned back hard, an inch or two from the ground in late spring after the frosts have finished. This is usually late May for most parts of the UK.
How to propagate Penstemon
Penstemon can be propagated by seed which should be sown in trays of seed compost in the greenhouse in early spring, but the new plants may not be a match to the parent plant. You may discover some interesting variations and growing from seed is both rewarding and fun. The easiest and most reliable way to propagate Penstemon to insure against any losses due to a harsh winter is by taking softwood cuttings.
Use a sharp knife to remove non-flowering shoots which are at least 10cm long, just below a leaf node. Remove the tip of the cuttings and the lower two leaves. Ideally, do this in the morning when your plants are well hydrated. Dip the bottom of the cuttings in hormone rooting powder or gel and pot them immediately into a small pot of compost with added perlite for aeration and drainage. You can place several cuttings around the edge of each pot as long as they are not touching one another.
If you are not able to pot the cuttings up straight away, then place them in a plastic bag sealing the air and moisture in if you can until you are able to pot them up. Water your pot and place it on a warm windowsill or greenhouse. Keep the humidity levels high with regular misting or place a clear plastic bag over the top for the first two or three weeks. A heated propagator or mat is useful for cuttings taken in spring when the weather is still cool. When you notice roots appearing at the bottom of the pot, your Penstemon cuttings can be potted on into individual pots. Tip your cuttings out without disturbing the roots too much and pot each one into its own container of compost to grow on, ideally in a greenhouse before hardening off and planting outside.