40 Perennials for the Best Summer Garden

25. Delphinium

There are blue flowers, and then there are these flowers. Delphinium is a traditional perennial flower in old English style gardens. Its stunning spikes covered in uniquely horn-shaped flowers bring an old-time charm to any garden bed.

Some alpine cultivars can reach up to six feet in height, making them ideal for a back border in a garden bed. Delphinium flowers are almost always a vibrant blue to violet, making them a truly stunning sight, especially at the upper end of their height.

26. Dianthus

Dianthus flowers are often referred to by the common names of Sweet William, Pinks, or Carnations. They are all flowering plants from the family Caryophyllaceae. What garden is complete without the beautiful, low mounds of Dianthus providing little pops of color in amidst the other foreground plants?

The delicate little five-petaled flowers are often shockingly neon pink, coral, and different bright, beautiful colors, and remain small and short enough to not overpower the plants around them.

27. Artemisia

Artemisia, often simply called Wormwood, is a stunning foliage plant that will bring a unique beauty to any flower garden. Many cultivars of the Artemisia family, which also includes herbs like Motherwort, are a beautiful silvery-grey with an almost powdery soft texture.

Despite resembling a bit of a winter wonderland, these summer plants do require full sun, so plan your garden accordingly. They also like well-draining soil as their slightly fuzzy texture is somewhat prone to rot.

28. Lamb’s Ear

If Artemisia doesn’t provide enough silvery, soft texture to your garden, just wait until you hear about Lamb’s Ear! As the name would suggest, the young leaves are incredibly soft and covered with tiny white, downy hairs.

A relative of mint, the plant also features adorable little pink flowers in tight clusters at the top of spikes, making it an absolute stand-out all season. As with Artemisia, be careful about draining and over-watering. You probably weren’t expecting to see a summery flower like this one on the list!

29. Balloon Flower

Few flowers will delight children more than the Balloon Flower. A hardy perennial that can grow quite far north, the attractive green foliage will support truly balloon-shaped buds that actually can actually be squeezed and “popped” open! Many of you probably routinely did this to your mother’s Balloon Flower’s as a child, despite numerous scoldings.

The unique nature of the buds, as well as the beautiful blue flowers, make this a must-have in any quirky or whimsical garden. It might even drive up a little nostalgia for those who have green thumbs throughout the family.

30. Bleeding Heart

Despite its somewhat ominous name, Bleeding Heart is a gorgeous addition to the mid-height range of any garden. It’s an incredibly elegant and whimsical plant, with outward reaching sprays of incredibly unique flowers, from what the plant takes its names.

The flowers are indeed heart-shaped, with one petal that stretches down, giving the impression that the heart is bleeding or dripping. Combined with elegant, deeply lobed dark green leaves, this plant is too beautiful to pass up. If you are looking for a conversation piece, this is the perennial you need in your garden.

31. Clematis

If you need a beautiful, flowering vine that won’t overgrow and try to eat the siding of your home, the Clematis is perfect for you. While some exotic looking vines like the Trumpet Blossom are showstoppers, they are not suited for planting near structures as they are quite destructive.

The Clematis can be a touch finicky and is a slower grower, but it will reward you with beautiful, large five-petaled flowers in a range of hues including multi-colored flowers. They are well worth the effort!

32. Foxglove

Foxglove is a strikingly beautiful plant. You probably glanced at this picture twice because it is simply that stunning. Even from a distance, the pile of large leaves radiating around the flower stalk is majestic, and the long spikes of brightly colored, speckled, bell-shaped flowers are inimitable.

This one-of-a-kind perennial is quite hardy and is a spectacular stand-alone planting in a rock garden. Toxicity note: foxglove contains an incredibly potent cardiac glycoside that is actually the source of the medicine digitalis, so handle carefully.

33. Hydrangea

Hydrangea is a beautiful flowering shrub. However, this perennial is also a fun science experiment for you or your children. The color of the flowers, rather than being determined by breeding like most flowers, is entirely dependent on the pH, or acidity vs. alkalinity, of your soil!

For true blue Hydrangea blooms, you need significantly acidic soil (a pH of 5.5 or less). For pink, the dirt must be neutral to alkaline (pH of 7 or above.) Anywhere in the middle, and you will have pink flowers. Did you realize it worked that way? Nature is amazing!

34. Roses

Of course you are familiar with this always popular perennial. Nonetheless, no list of beautiful summer perennials could ever be complete without mentioning roses. While roses have often had a reputation as fussy, difficult plants, many new cultivars are bred specifically for the casual home gardener and not the experienced rose gardeners of old.

The price of roses is also quite reasonable, now, with many healthy large bushes starting at only $10 to $15. There’s never been a better time to try introducing roses to your garden but, as always, mind the thorns! You might get pricked once or twice, especially if you are a beginner.

35. Liatris

Liatris is a stunning, showy perennial with stalks of whispy purple flowers that survives through a unique means: corms! Corms, yes with an m, are short, vertically oriented tubers. Other bulbs that overwinter through corms include some varieties of Iris, Gladioluses, and crocuses.

If you are living in a cold climate, you can dig up the corms and overwinter them in a root cellar or another cool, dry place, making them a versatile choice. You can still have a summery garden even if you live in a chilly location thanks to this perennial!

36. Poppy

While many varieties of Poppies, including the infamous Opium Poppy, Papaver somniferum, are not hardy in the United States, there are varieties, including the Icelandic Poppy, that can overwinter even in harsh conditions. The Icelandic Poppy, as its name might imply, cannot tolerate heat so gardeners in widely variable climates like the

Just as the name sounds, Midwest gardeners should avoid this variety as it could get scorched. More temperate climate gardeners, however, will be rewarded with papery, delicate flowers on comically long, prickly stems.

37. Sweet Woodruff

Few shade-loving perennials are most all-around pleasant than Sweet Woodruff. Indeed, this is a plant content to mind its own business and thrive, neither being aggressive nor invasive, it spreads at an even, moderate pace but rewards a patient grower with a lovely, low carpet of sweet-smelling flowers and dark green almost way foliage.

It’s a somewhat tender perennial above USDA zone 5, so northern growers should pick a sheltered place to plant it. Sweet Woodruff, Astilbe, and Hostas together are all you would need for a truly stunning shade garden.

38. Creeping Thyme

Another excellent ground cover, it’s hard to beat Creeping Thyme’s versatility and delicate beauty. A very hardy perennial, Creeping Thyme spreads similarly to a mint through a trailing, horizontally vining habit. It can cover large areas relatively quickly and is also easy to start from seed over large areas.

It most commonly has abundant purple flowers, which make a beautiful backdrop for any other flowers it surrounds. It can’t tolerate full shade but can fill many other hard to cover areas. If you love the magenta shade, this is the flower for you!

39. Giant Allium

If you’re looking for a showstopper with surprisingly long-lasting flowers, look no further than the Giant Allium. As the Allium part of its name suggests, it is indeed related to garlic, onion, and other members of the Allium family and its flowers show that relationship.

It emerges early in spring and quickly fills in its growing area with vibrant green leaves reminiscent of tulip greens. The flowers last up to several weeks, depending on weather, and are incredibly eye-catching. In the beginning of summer it rewards gardeners with huge globes covered in small purple flowers at the top of long, thick stems.

40. Hellebore

Despite numerous common names that reference roses like Lenten Rose, Winter Rose, and Christmas Rose, the Hellebore is not a rose at all and is, in fact, a member of the Ranunculaceae family which does not include roses. Lenten Roses are a truly stunning flower, with incredibly unusual flower shades that include greens, beiges, browns, and other rare hues.

They bloom early in the spring, and some varieties have evergreen foliage. Northern gardeners will have to shelter these plants to overwinter, as they are only hardy to USDA Zone 5. Toxicity note: all parts of Hellebores are toxic, and some gardeners may experience skin reactions.