Top Ten Summer Flowering Perennials

I have pulled together a list of some of our favourite garden additions that have proved not only reliable but worthy assets to any garden or outside space. There is a reason we see these plant picks being used throughout the horticultural world from magazines to garden shows, Chelsea to Gardeners World. Take it from me these are definitely some potential beauties for your garden whether you are trying to create a romantic, traditional style English garden or chic contemporary courtyard…

Echinacea purpurea

A hardy perennial that does not require much maintenance these bright pink flowers pop into life later in the season. They not only look good dotted through mixed perennial beds, used as a contrast of colour, but can be bold additions amongst ornamental grasses or prairie style planting, they also make great cut flowers!

Eventual Height
1.5m
Eventual Spread
0.45m
Position
Full Sun
Soil Type
Any
Flowering Period
June – September
Hardiness
Fully Hardy

Verbena bonariensis

Tall slender stems hold purple pom pom flowers aloft seemingly floating in the air. With a long flowering period throughout the summer this perennial is useful in several situations; sheltered courtyards against a wall, amongst prairie grasses, or at the front of borders – due to their thin stems they do not obscure the planting behind. Cut back in Spring rather than Autumn to help give it some winter protection.

Eventual Height
2m
Eventual Spread
0.45m
Position
Full Sun
Soil Type
Moist and fertile but well drained
Flowering Period
June – September
Hardiness
Moderately Hardy – may need winter protection – but does self-seed particularly well.

Salvia nemorosa ‘Caradonna’

If you have struggled with Lavender due to moist conditions in the past, but enjoy it’s visual effect then this hardy Salvia may be the perfect option! This mound forming herbaceous perennial has tall spires of dark purple flowers, planting alongside other purples, whites and lime greens can create a fresh pallet that will last throughout the summer. To prolong flowering cut flowers off as they begin to go over.

Eventual Height
0.5m
Eventual Spread
0.3m
Position
Full Sun
Soil Type
Moist and fertile but well drained
Flowering Period
June – October
Hardiness
Full Hardy

Veronicastrum virginicum ‘Fascination’

Tall and elegant this variety of veronicastrum produces delicate racemes of lilac purple flowers. This tall perennial is a useful addition to the back of beds or as a screen between different garden areas. We have used it alongside the Hydrangea ‘Annabelle’, the soft spire like flowers of the veronicastrum and its pastel purple contrasts effectively to the bold round mop head of the white hydrangea.

Eventual Height
1.8m
Eventual Spread
0.45m
Position
Full Sun or Partial Shade
Soil Type
Moist and fertile but well drained
Flowering Period
June – August
Hardiness
Full Hardy

Hydrangea arborescens ‘Annabelle’

A Hydrangea variety becoming ever more popular due to its attractive large compact mop heads of small white/cream flowers. They work in groups or dotted as individual plants either in a traditional ‘English country garden’ schemes or a softer addition to a contemporary courtyard. As with any Hydrangea variety they do not like to dry out so keep well-watered! By leaving the flower heads over winter they not only provide a textural structure throughout the colder months, and look attractive when covered in frost but the best time to prune is in February. Low maintenance plants that need very little care they are a welcome new take on an old favourite.

Eventual Height
2.5m
Eventual Spread
2.5m
Position
Full Sun or Partial Shade
Soil Type
Moist and fertile but well drained
Flowering Period
July – September
Hardiness
Full Hardy

Crocosmia ‘Lucifer’

With lush green foliage that produce small bright red flowers on delicate stems these are effective when planted in swathes together. As part of a ‘hot colours’ bed they are a must have and can be contrasted with colder colours for a dramatic effect. They make very effective cut flowers. Similarly with Verbena, leave the foliage over winter and cut back in spring when the weather starts to warm up.

Eventual Height
1m
Eventual Spread
0.1m
Position
Full Sun or Partial Shade
Soil Type
Moist and fertile but well drained
Flowering Period
August – September
Hardiness
Frost Hardy

Astrantia major

Astrantia comes in many different colours from white to claret red or soft pink. If the old flower stems are removed this can prolong flowering time, fresh or dried flowers are perfect in arrangements. The darker coloured blooms are very effective in prairie style planting as the star shaped flowers contrast well with softer ornamental grasses and have a more robust form than many wildflowers. The white varieties can look very effective planted amongst ferns and hostas to create a fresh clean accent amongst lush greens.

Eventual Height
0.9m
Eventual Spread
0.45m
Position
Full Sun or Partial Shade
Soil Type
Moist and fertile but well drained
Flowering Period
June – August
Hardiness
Full Hardy

Geranium ‘Rozanne’

A Chelsea Award winning perennial there is no doubt that this variety of Geranium has gone from strength to strength winning over horticulturalists everywhere. A vigorous spreading plant it can provide effective summer ground cover, the bright blue flowers work well planting under white hydrangeas or as a companion to roses. The flowers will climb and scramble over the shrubs for a wildtop ten look or can be used to tumble over the side of large containers. Cut back around the time of Chelsea flower show to rejuvenate the plants and provide a longer flowering period into later Summer.

Eventual Height
0.6m
Eventual Spread
0.8m
Position
Full Sun or Partial Shade
Soil Type
Moist and fertile but well drained
Flowering Period
June – October
Hardiness
Full Hardy

Eryngium zabellii ‘Big Blue’

Commonly known as ‘Sea Holly’ these stunning flowers provide an alternative texture to a herbaceous bed or work well in ‘cool’ colour schemes. With bright blue flowers that fade to silver towards the end of the summer they provide a blue haze on those late summer evenings. They are great dried flowers and very popular amongst the pollinators in our gardens!