Surprisingly, there are not too many shrubs that actually flower right through the summer months, though of course there are many shrubs which are colourful through summer byway of attractive foliage - normally variegated. Shrubs generally have a shorter flowering period than many of the herbaceous perennials. So out of the many thousands of shrub types, I will try to choose those that bloom all summer. There are many more summer flowering shrubs of course that flower for just a couple of weeks.
Firstly, let's define when summer actually starts - and ends. The generally accepted months are of June, July and August. This is true of the southern part of the UK, but would have to move the starting date from the 1st of June by one or two weeks as we move further north.
Summer, if perceived as being sunny weather, can be extended or contracted by a month or so in either direction dependent upon the type of weather available. Plants and shrubs in particular, are more governed by the calendar dates and day length at this time of year, though in spring, their flowering time can be related to temperature. Realise also, that where you plant your shrub will also have a bearing on when it flowers, and also for how long!
So agreeing that summer is in fact just 3 months long, helps me with my shrubs for summer flowering list. I will then have to do a further list for late summer, early summer, and of course simply 'summer' for those that put in an appearance for just a few weeks! Then there are the other three seasons. But, that’s my problem, not yours!
The top Ten List of Summer Shrubs that flower throughout the summer, are of those that can be reliably expected to flower for most of the three months. Below that, there are shrubs which will be expected to flower for at least two of the summer months.
Some will require such mundane – but important – cultural activities such as dead heading or lightly pruning out the old flowered stems. Others will flower forth regardless.
This shrub - the mallow - will be regarded by some as being as common as muck. Rightly so and a great compliment, for it shows how popular it is. This would be high on my list for any shrub border or even a single shrub to flower all summer, and beyond.
A shrub that deserves to be more widely grown. Not the hardiest, so will need a woodland setting unless in one of the milder areas. Masses of small red lantern flowers throughout the summer. Will also benefit from a slightly acid soil.
A small arching shrub well suited to growing in a sunny border or at foot of wall or fence. Get it through the first winter with a bit of protection and it should be reliably hardy in a dry-ish soil, and will show off its pendant red and yellow flowers throughout summer.b Abutilons
The Weigela - pronounce it how you want - is a reliable summer flowering shrub with shades of pink or cerise to choose from. Weigela florida Nana gives pink flowers with the additions of god variegated foliage thrown in. Weigela florida 'Foliis Purpureis' is good dark purple foliage - best in light shade.
Evergreen as well as summer flowering, makes this a worthwhile addition. Great at the seaside as well with white through all shades of pink to deepest red flowers to choose from. Stand alone shrub or with shelter away from spoiling winds.
These should not be confused with the blue flowering evergreen Californian Lilacs which have a relatively short flowering period. Ceanothus 'Gloire de Versailles' is deciduous, needs annual pruning, and will flower with large pink flowers for most of the summer.
The Spanish Broom will reward you with masses of bright golden yellow flowers with as long a flowering period as the Lavatera. That is not suggesting that its golden yellow will blend next to the shocking pink of the Mallow. But, up to you!
This one can rightly claim to be a shrub. Long stems of drooping tubular flower in rich pink or pale red - depends how you see things. It needs shelter and light in non waterlogged soil.
Evergreen flowering shrub, with long racemes of rose lilac flowers - turning white. Really benefits from dead heading the flower weekly, and then will show off well into autumn.
Depends where you live as to what variety you can class as hardy. The slender drooping flower of Fuchsia ricartonii will reward you with months of flowers more or less anywhere in UK.
The Roses are often overlooked as being shrubs - and long summer flowering shrubs at that. Go for any of the floribunda types for best succession of flower, and dead head all the blooms. Stay clear of some of the favourite shrub roses for these generally have a shorter flowering period.
Abelia grandiflora types are dead certs for blooming through the summer months and are also evergreen with very attractive foliage. Abelia Francis Mason had the added advantage of gulden variegated foliage.
The shrubby Potentillas seem to have flowers at any time of the summer through till autumn. The main flush of flowers happening in late may or early June, followed by lesser - though dependable - outbursts of blooms later. Many colours to choose from, with yellow being the predominant colour. However cream, pink, primrose and orange hues are also available.
The taller growing Hypericum Hidcote - rather then the ground cover Hypericum calycinum - is the one to go for if you are after the golden yellow buttercup flowers that adorn this bush.
The English Lavenders are hardier than the French frilly ones, and have a multitude of uses in the garden or container. The secret is a dry well drained soil, especially during the winter months. How to grow Lavenders
Steer clear of the white flowered types if you want a full summer display, and choose Spiraea Anthony Waterer or one of its variant for long flowering period. The golden foliaged Spiraea Goldflame lives up to its name, with flowers after the many early show of dazzling shoots. Spiraeas
Masses of gaudy flowers on this summer flowering choice. Needs particular growing position, and will then reward you for that.
The butterfly bushes of the Buddleia davidii group will flower continuously from June if you regularly remove the faded blooms. Buddleia x weyeriana will also oblige. Buddleia Page
If you can grow it, and find it, Erythrina is quite spectacular, and will certainly be a talking point with visitors.
The Bottle Brush shrub is hardier than realised, but needs a dry sunny position.
After its main flush of late May flowers, this Magnolia will rarely be without a bloom or two in summer. Ignore the other magnolias for summer, for they are generally a quick flash in April/May.
Long flowering and a sun worshiping gem. Cistus purpureus is the best of the group. Show deep pink blooms.
The Bladder Senna, has yellow flowers and attractive pinnate leaves. After flowering for the most of summer it will develop attractive green seed pods, which then turn translucent.
The type mentioned above is one oif the hardiest. The unusual flowers, require the plant to grow on either acid or neutral soil. Well drained and certainly not long periods of cold wet soil in winter.
The Curry Plant for a dazzling silver foliage display and yellow flowers. Oh. And the spicy aroma of brushed foliage which gives it its common name.
This is not one of the climbing Jasmines but more of a stocky shrub. Good foliage with yello – unscented – flowers through most of summer.
This of course is for an early flowering display, but will also have a few blooms thoughout the summer. The basic single flowed version rather than the double 'flore plene' will do this best.
Leycesteria Formosa is one of mu favourites – not least because it can be cut back to ground level eauch year. The common name of Himalayan Honeysuckle is not as descriptive as the common name of Pheasant Berry. Red flowers through Summer, with attractive foliage on long arching slightly stems. Flowers well into autumn when the berries take over.
Lowes growing shrub with brightes blue flowers will adore a sunny position not overshadowed by others, though peeping from under a larger shub also suits.
Santolina chamaecyparissus or cotton lavender if you wish is the best silver foliage in this group. The yellow pompom flowers stand proud, but it needs a sunny position that is dry. Cut back right after flowering to give the flower buds time to develop for the next year.
Clematis tangutica types Cl
Solanum crispum Cl
Jasminum officinale. Cl