Hebe: how to grow, when to prune and which to plant

What is a hebe?

Hebes are a genus of about 90 species of evergreen, long-flowering shrubs, some with coloured foliage that tend to form dense hummocks. Hebes were originally classified as species of Veronica, and more recent analysis has shown them to indeed be part of the Veronica genus where they may soon be moved back.

Most hebes originate in New Zealand with a few species scattered around the southern hemisphere. A hebe’s flowering period is from midsummer to mid autumn, with most flowering between June and September.

They can grow between 40cm to 1.5m, and most hebes prefer poor, well-drained soil. They will withstand high winds and salt spray. Although some hebes are hardy, others can suffer from frost damage to new shoots. Most have a hardiness rating of RHS H3 or RHS H4 and are suitable for gardens in USDA zones 8a to 10b.

When to prune hebe

A light, annual pruning will keep the neat, compact shape of hebes and ensure that they flower well. Immediately after they have finished flowering simply cut out the dead flowers. After a harsh winter some stems may have been burnt by frost. Inspect your hebes at the end of March and prune away any damaged stems, cutting back to a live bud. I have seen small-leaved hebes tightly clipped into balls as an alternative to box. This looks attractive but does mean that the flowers are sacrificed.

How to take hebe cuttings

It is ironic that a plant named for the Greek goddess of youth should be short-lived. Although some hebes will still be looking good after a decade or so, most will perform at their best for a shorter time and then need to be replaced. Hebes are one of the easiest shrubs to take cuttings from, so rather than buying a replacement plant, have a go at propagating your own. Begin the process as soon as your hebe starts to look sad, and by the time you need to remove it you will have a new plant ready.

Cuttings can be taken from mid July until early September. Using sharp secateurs, cut off stems of the current season’s growth that are about 15-20cm long. Immediately pop these into a plastic bag and keep them in the shade until you are indoors and ready to pot them.

Fill your containers with a proprietary cuttings compost or a mix of 50 per cent compost and 50 per cent horticultural grit, then water the pot and allow it to drain. A 9cm pot will take three or four cuttings. Prepare the cuttings by shortening them to about 10-15cm long, cutting just below the point where a set of leaves is growing. Remove the lower leaves and snip off the tip of the cutting. Push the cutting into the compost, close to the edge of the pot.

If you want belt-and-braces security, you can dip the end of the cutting in hormone rooting powder or rooting gel. If you have a greenhouse or cold frame, store the cuttings there, otherwise cover the pot and cuttings with a plastic bag in a light, warm place away from direct sunlight. Regularly remove the bag to reduce the humidity around the cuttings. By the following spring, the cuttings will have rooted and can be transplanted into individual pots filled with a loam-based potting compost.

Hebe soil

Hebes need poor, well-drained soil in an open, sunny situation. Ignore the usual advice to incorporate compost when you plant shrubs and don’t give them an annual feed. Too rich a soil will encourage weak, lax growth that will be susceptible to frost damage. If you have heavy soil, digging lots of horticultural grit into the area before you plant will increase the likelihood of your hebe thriving. Hebes do not like cold wind, so try to plant them in a sheltered area.

Why plant hebe?

On paper, hebe plants have a lot going for them – they are long flowering, easy to grow, and evergreen. Nevertheless, despite their many qualities, they are not in fashion. Why this should be is rather puzzling; surely they deserve more recognition.

Part of the reason might be that some designers have not yet found a place for neat domes of a hebe in the naturalistic froth of perennials and grasses that currently dominates their work. Moreover, they have a reputation for being short-lived. There are signs, however, that the tide is starting to turn in the favour of hebe as dynamic breeders are starting to produce new cultivars, often with notable foliage.

Most hebes form hummocks that can, with a little imagination, be used in many garden settings. Some can be clipped into neat domes that are at ease among the clean lines of contemporary gardens. I have seen the solidity of groups of dwarf hebes looking wonderful as a background to clouds of Sporobolus heterolepis. It is a combination that would work well with other grasses and airy perennials. Low hedges of hebe are often used as a windbreak in exposed coastal gardens and the same planting could be used to protect and enclose herbaceous plantings in inland gardens. Some of the newer introductions have been specifically bred for pots and containers and for small, urban gardens. It remains to be seen whether hebes become sought after but a plant that is so versatile and so beautiful should nevertheless be seriously considered in any garden.

The best hebe plants for your garden

A hebe that is a truly spectacular sight during the winter when the narrow, lance-shaped leaves turn a vibrant burgundy colour. During the summer the foliage is apple-green and the flowers are a delicate pale blue. 50cm. AGM*. RHS H4†.

A striking plant launched two years ago that has variegated foliage comprising oval, grey-green leaves with wide, cream margins. The new growth has dark stems and pink-edged leaves, which complement the purple flowers. 1m. RHS H3.

A dense, rounded shrub with small, elliptical, glossy leaves, about 1cm long, that resemble those of boxwood. The pale-lavender flowers appear at the tips of the stems in July. A robust cultivar that requires little maintenance. 30cm.

Grown primarily for its colourful foliage. During the summer the leaves are green with a white border but in autumn they turn pale purple and pink. Lavender-coloured racemes of flowers in summer. 75cm. RHS H3.

60cm. RHS H4.

The combination of green and cream variegated foliage and dazzling, bright-white flowers attracted a lot of attention when this cultivar was first introduced in 2018. 1m. RHS H3.

Raised by Lowaters and introduced in 2013, this was selected for its compact shape and bright-green foliage. Masses of pale-blue flowers on upright spikes appear for about six weeks in midsummer. 50cm.

A popular hybrid that was introduced in the 1960s. The glaucous leaves have a red margin that becomes even more pronounced in winter. The small flowers are pale mauve. 60cm. AGM. RHS H4.

A large and floriferous shrub with glossy, green foliage that is covered with soft-pink flowers from July through to October. The flowers fade almost to white as they age. 1.2m. RHS H3.

A startling sight in winter when the glossy, green leaves turn deep purple, sometimes looking almost black. The flowers appear from June to August and are a purplish-pink colour. 75cm. RHS H4.

A compact, rounded plant that is ideal for a container. The striking, dark-green leaves have a red edge and are entirely plum-coloured when they emerge. Violet flowers from late spring to early autumn. 60cm. AGM. RHS H4, USDA 7a-10b.

A low-growing, compact hebe that makes a good flowering plant. The flowers are pink in bud, opening to a pale lilac and fading to white. An early flowering form that blooms in April and May. 40cm. RHS H4.

Where to buy hebes

• Ashwood Nurseries, Ashwood Lower Lane, Kingswinford,  West Midlands DY6 0AE. Tel 01384 401996, ashwoodnurseries.com

• Burncoose Nurseries, Gwennap, Redruth, Cornwall TR16 6BJ. Tel 01209 860316, burncoose.co.uk

• Garden Cottage Nursery, Tournaig, Poolewe,  Wester Ross IV22 2LH. Tel 01445 781777,  gcnursery.co.uk

• Lowaters, Plants from this specialist hebe breeder can be purchased by mail order through its Garden Beauty website.gardenbeauty.co.uk