Late Summer Flowering Shrubs

by | Aug 18, 2021

Is it a little bleak in the colour department of your garden right now? Vacillating hot (extremely hot) and cool weather certainly hasn’t helped our gardens, and many plants have struggled to stay lush amid the stress. Many seasonal plants have succumbed to the conditions, and it will be a while yet before deciduous trees start to take on the lovely hues of fall. To fill the void (and to give yourself something to look forward to at this time each year!), consider adding some of these amazing late summer flowering shrubs to your yard!

buddleia flower


At the top of the list are the new varieties of butterfly bushes – beautiful buddleias! The old tall, woody and invasive varieties have given way to a whole new series that not only adds long-blooming colour and perfume to your garden but also attracts butterflies and honeybees too! The smallest and cutest are the ‘Lo & Behold’ and ‘Pugster’ types that grow approximately 24-36” tall and wide, making them ideal for patios. They play well with other small shrubs, with perennials, and annuals to boost the colour in any garden. A little taller in the 4-5’ range are ‘Miss Molly,’ a stunning ruby red and ‘Miss Violet,’ the purplest purple – talk about impact!


Perhaps the most unusual summer-flowering shrub is calycanthus with its beautiful magnolia-like blooms. It has red, slightly perfumed flowers that, once established, will rebloom in late summer to early fall. Growing only 5-6’ tall and wide, its shiny foliage is quite remarkable and very unique. Its blossoms will turn heads. 


Also known as Bluebeard, caryopteris is heat and drought-tolerant and attracts hummingbirds, bees, and butterflies, making it a great addition to your pollinator garden. Bottlebrush-like blooms are blue/indigo in colour, and foliage is either green or chartreuse. They typically grow about 30-36” high and wide and are hardy to zone 5. Caryopteris blooms from late summer through to early fall. 

daphne eternal fragrance

Daphne ‘Eternal Fragrance’ 

Daphne offers incredibly fragrant blooms from late spring to early fall and has a nice, compact form (only growing about 2-3’ high and wide). Foliage is evergreen. Be cautious though; daphne is toxic. 


Growing to about 15’, this large flowering shrub (or small tree) bears unique, fragrant, seven-part flower clusters, usually starting in September. They age beautifully through the season, with calyxes turning a rose-pink colour as they mature. Showy purplish-red fruits appear in the fall, and the tan bark exfoliates to reveal pretty brown inner bark, making it quite attractive in winter too. It really is a beautiful tree! 

Hibiscus (Rose of Sharon) 

Where would you find another shrub, other than a hibiscus, that starts blooming in July and goes until October? Although we’ve had them forever, they still need to be planted in more gardens. Today, there is such a wide range of colours in both the single and double blooms, but ‘Red Heart,’ a large single white with a red throat, really stands out in the garden. The large-flowered double ‘Chiffon’ series is quite remarkable too, and many of the new varieties named after the South Pacific islands, like ‘Fiji’ and ‘Hawaii,’ have beautiful flower combinations. ‘Purple Pillar,’ a newer columnar variety with nice lavender flowers, fits beautifully into small space gardens. Perennial hibiscus, like the ‘Summerific’ Series from Proven Winners, are absolute stunners as well, but they do die back to the ground each year.


The sun and heat-loving hydrangeas have really come a long way. The PeeGee hydrangeas, the ‘big guys,’ like ‘Pinky Winky,’ ‘Zinfin Doll,’ ‘Strawberry Sundae,’ and ‘Quick Fire,’ are all stunning pink and white combinations that grow 6-8’. Up there too is the amazing ‘Limelight,’ a beautiful lime turning cream then pink. Downsizing has thankfully happened, giving us ‘Little Lime,’ ‘Little Quick Fire,’ and ‘Bobo,’ all in the 3-5’ range. They will make perfect summer companions in containers or as icons in small space gardens. 

daphne eternal fragrance


We can’t have an article on flowering shrubs without mentioning roses! Many folks associate roses with June and the peak of summer but, when well-tended, they will continue to flower through to frost. Heck, some ‘Easy Elegance’ varieties boast blooms into October and even longer! Roses that leave behind significant rose hips add even more colour to the garden later in the season!

daphne eternal fragrance


(Clethra alnifolia rosea) is an August bloomer with tiny pink bottlebrush-like flowers that have a lovely perfume. Their fall colour is also magnificent. Depending on the variety, clethra can grow up to about 6-8’ high and wide. 



(Itea virginica) is loaded with long white cascading flowers that add a lovely fragrance to the summer garden. There are a few varieties, and all are quite small (3’ x 3’), fitting easily into small spaces. They also have wow fall colours.

Planted carefully now, and watered deeply and regularly until they are established, these shrubs will be well settled in your garden before the dormant season. When planting, be sure to dig a hole one-and-a-half to two times the size of the planting hole, and amend your soil with fine fir or hemlock bark mulch to improve drainage. Add some bone meal to the planting hole, and water in with a liquid transplanter to get them off to a solid start. Should we experience dry spells again next spring through fall, remember to give your new shrub a good, deep drink around the drip line to keep it growing strong.