Most Hebes need little or no pruning. However the larger-leaved types are prone to damaged stems, and these can be safely cut back at any time during the growing season.
Dead-heading of old flowers on Hebe plants is well worth the effort. It can extend the flowering period, or encourage a further show of flowers later in the year. If your particular plant becomes straggly, then cutting back hard - to within 30cm of the ground - will rejuvenate it. However, this last option should be done with care! See below.
As with the vast majority of flowering evergreen shrubs, Hebe shrubs should be pruned in the growing season - or right at the end of the winter dormancy period. They should not be pruned in late Autumn - nor winter months.
When pruned well - and sparingly - these shrubby Veronicas can enhance any garden - or container. There are easy maintenance, generally trouble free flowering evergreens that just need a bit of sprucing up occasionally. This is what you do - and when.
Hebe eliptica. This and other similar Hebe bushes, often suffer from snow damage, which opens up the centre of the shrub and often causes some of the branches to snap off under the weight.
Normally it is enough to simply cut out the damaged stems, and regardless of the shape after doing so, it will soon regain the compact habit of growth for which they are known. After flowering - which can be quite prolific, the fade trusses should be snipped off. This will allow flush of new growth - and also prevent the untidiness of this particular variety going to seed. Allowing the seed heads to develop will also take away some of the vigour from the shrub.
Hebe Midsummer Beauty and other similar long leaved Hebe varieties, generally require no pruning other than cutting out winter damage. However, the shrubs tend to get a bit top heavy, with bare stems at the bottom of the bush.
Cutting back a few of the older stems to low down - near the base, will allow new branches to form, which will better clothe the shrub from top to bottom. Dead heading of the flowers as soon as they fade, will ensure continuation of the flowering period.
Hebe Tricolor is one of the less hardy types of Hebe shrubs that will probably have to be cut back quite hard after a hard winter. There will normally be new shoots emerging from lower down the stems, so pruning back any dead wood should stop at the new growth buds. These will soon break out to form new branches.
However, larger growing varieties can suffer damage in winter months - either by weight of snow or severe frost damage. In this case, if it is not sufficient to prune out the damages stems/branches, they can be cut back quite hard. This is best done in two stages. Firstly cut around one third of the branches quite hard, then when the these start to re-generate into new growth - usually after just a few weeks - the remaining two thirds of the branches can be pruned out.
There will be no need to prune the smaller leaved varieties - other than a light trim to shape them and perhaps promote a little more growth in the centres of the ground huggers.
By far the most important pruning operation that can be carried out with the larger leaved/flowered varieties, is to regularly dead head to faded flowers. This light prune - if it can be so called - will prolong the flowering period my several months in some cases. Some varieties of Hebes, such as the so-called whipcord varieties, will probably need a regular spring prune after the first year of planting. Otherwise they tend to get a little leggy with unsightly lower stems. A compact habit is far more desirable and hard pruning back will ensure this.
In this section, we are concerned with Hebes that are grown as shrubs. The shrubs in this wide group are normally evergreen with varying degrees of winter hardiness and generally attractive flowers. There are also some variegated types and with otherwise coloured foliage - particularly silver types.
Hebe – pronounced ‘Hee-bee’ is derived from Greek mythology where Hebe is the Goddess of Youth. The main common name for the Hebe group is Veronica – an older term that was brought about by Hebes being grouped in the Veronica main family. Nowadays, they are Hebes, with the veronicas being a group of perennial plants – distinct from Hebes, though with somewhat similar flowers.
Hebes are known for their spikes of flowers, with many individual flowers making up the main flower spike. The leaves are normally set in groups of four around the stem with two opposite pairs set above each other in every grouping of four.
Hebe shrubs should not be planted in areas of long freezing cold winters, and are generally more suited to milder areas. Much depends upon the variety of Hebe, with the smaller leaved plants- especially the prostrate Hebes - doing better in cold areas.
It is not easy to generalise about Hebe shrubs, for they have a wide range of growth habits, including small to medium heights and flower colours from pure white through blue and pink shades to deep red.
As with many of our most popular shrubs, Hebes mainly originated from New Zealand, but some also from the south of Australia and others from southern Americas. Their range of natural habitats make them interesting for many different garden applications, and a wide range of locales, in particular, coastal areas where the salt-laden winds are so often lethal to many plants.
In short there are Hebes which are suitable as specimen, container, border, rockery and groundcover situations and hedges. There are very few plants where the general planting advice, is to plant in poor seemingly lifeless soils. Hebes are one of the few.
Soil type seems not to matter as long as there is reasonable drainage. Otherwise a wide range of ph levels is acceptable, and i have planted and grown most type in most soils. Such versatility!
The suitability for different planting places can be governed by a little knowledge upon the original habitat.
That having been said, most I have grown in what I consider to be ‘normal’ gardening areas, without any problems.
Flowering period depends upon the variety of individual Hebe, and can start in early summer with some varieties lasting well into the Autumn or even early winter.
Flowering period can be prolonged by regular removal of faded flowers, which encourages a further flush of blooms.
The full range of Hebe plants are attractive for a wide range of insect life – in particular for those with physical make-up to reach inside the somewhat tubular flowers of the larger flowered varieties. Bees, butterflies and many other beneficial and attractive flying insects are attracted. Because of the vague similarity between Hebe and Buddleia flowers they are sometimes erroneously called butterfly Bushes, which of course is the accepted common name of the Buddleia.
The main consideration when planting Hebes is that they are best planted away from cold, drying winds that can sometimes scorch the foliage - especially in cold winter areas. Full sun or slight shade is suitable for all types including the dappled shade in light woodland areas. The low growing silver foliage types are best in open aspects, where they will not get smothered with fallen leaves in autumn and winter.
In any new garden or planting scheme, Hebes are one of the first that come to mind, not simply as a personal preference, but in the realisation that Hebes rarely fail to please or fulfill the function they have been included for.
Add to all this the fact that Hebes are easy to propagate from cuttings, sometimes set seed in situ, and rarely have problems of a serious nature, you will soon that the Hebe group of shrubs is one not to be ignored .