Want to add a splash of color to a late summer garden?
Dig into some of the best flowers for late summer in Colorado—whether you live in Denver, Colorado Springs, Grand Junction or another lovely Colorado town!
These late summer flowers bloom in August, September and some into October. They’re ideal if you’d like to:
- Add beautiful color and texture that will have neighbors taking notice.
- Attract pollinators to your garden, like hummingbirds and bees.
- Reduce the amount you have to water. (Yay for less work—and less water! They’re all drought tolerant plants.
They’re all perennials, so they should return for multiple years. They prefer sunny spots that get 6+ hours of sunlight per day.
If you live at a higher elevation in Colorado (or a similar western state), your growing season may not be long and warm enough for these late summer and early fall flowers. But good news, you can find a list of flowers for mountain gardens from the Colorado State University Extension.
Let’s jump in!
The best flowers for late summer in Colorado include…
Hummingbirds adore Sunset Hyssop. This late summer flower is Grand Central Station for hummingbirds. You may notice butterflies, bees and sphinx moths visiting it too. And bonus, this plant is typically deer and rabbit resistant, meaning Bambi will likely visit your neighbors’ gardens first.
Sunset Hyssop is one of the more reliable hyssops in Colorado when it’s planted in sunny, well-drained locations. Translation: It has a good track record of returning when other hyssops may not! Its salmon-orange flowers tend to be the showiest in August, but you should see blooms into fall.
Sunset Hyssop is native to the mountains of the Southwest. Zones 5-10.
Not familiar with “zones?” Learn what a hardiness zone is and how to find your zone here.
Dakota Sunshine Maximilian’s Sunflower
Helianthus maximiliani ‘Dakota Sunshine’
If you like sunflowers or you simply like daisy-like flowers, this may be one of the best flowers for late summer in your garden! Dakota Sunshine gets spires of showy yellow blooms that grow up tall stems. It’s a drought-tolerant perennial that can reach 5’ to 6’ tall, so it’s ideal for adding height to the back of a garden.
Native to the prairies, Dakota Sunshine blooms in August into early September. It’s a favorite of bees when it’s blooming. When it goes to seed later in the fall, the seedheads attract birds. Zones 3-8.
If you’d like a version of this plant that blooms in the fall, look for Maximilian Sunflower. It grows even taller—often 6′ to 8′ in height—and typically blooms in September and October in western states like Colorado.
I found Dakota Sunshine at High Country Gardens. You also may be able to find these plants at local, independent garden centers.
Autumn Joy Sedum
Sedum spectabile ‘Autumn Joy’
So many reasons to love Autumn Joy Sedum, so little time! This perennial has beautiful pink flowers that appear in late summer and last into fall. Honeybees love the flowers.
Autumn Joy has thick leaves that add great structure and textural contrast to a garden. It tends to be a longer-lived perennial, coming back for many years. It adapts well to our tricky Colorado weather and soils (dirt). And during the winter, its seed heads can catch snow, adding interest to your winter garden too. Zones 4-11.
Meadow Blazing Star Liatris (aka, Rocky Mountain Gayfeather)
When I’m strolling through the Denver Botanic Gardens in August and September, this is the plant I usually hear people asking about. It’s an attention getter.
Blazing Star Liatris sends up vertical shoots of rosy-purple flowers that look like fuzzy buttons. The narrow, vertical shape of this plant offers a nice contrast to round-shaped plants in late summer gardens. And its flowers are extremely attractive to adult butterflies, including Monarchs. In my garden, Blazing Star Liatris also attracts native bees—particularly bumblebees.
If you see the words, Liatris punctata (Dotted Blazing Star) or Liatris ligulistylus (Meadow Blazing Star), on the plant tag, your plant is native to Colorado and the Central Plains. Zones 4-9 and 3-8.
If you see Liatris spicata (Dense Blazing Star) on the plant tag, it’s native to the eastern United States. It tends to prefer more moisture.
Goldenrod puts on a show with its vibrant, golden flowers in late summer and early fall. There are many species of Goldenrod that are native to different parts of North America, and you can find them in a variety of heights. Look for Goldenrods that bloom in August and September.
Goldenrod flowers are extremely attractive to a wide variety of pollinators, including bees and butterflies. In my garden, tiny native bees love these plants. Zones 4-8.
Goldenrod has been blamed for seasonal allergies like hay fever, but this is a garden myth that has been disproven. The allergy-causing culprits are typically wind-pollinated plants like ragweed, which happen to bloom at the same time.
Little Bluestem Grass
Ornamental grasses are in their glory in late summer and early fall. One of my faves is Little Bluestem.
It has a column-like shape rather than a round, mounded shape, so it fits in well in small urban gardens, as well as spacious western landscapes.
Native to Colorado (and the prairies of much of the United States), many varieties of this blue-green grass turn a red color in the fall, making it a wonderful accent to other plants. During winter, it can take on a bronze hue with light seed heads, so it can add colorful interest to your winter garden too. Zones 3-8.
Ruby Muhly Grass
If you’re looking for a late summer flower that’s a showstopper for your Colorado garden, check out Ruby Muhly Grass. It has airy, pink seed heads that dance in the wind and catch the late summer light. It’s ethereal! And it’s another ornamental grass that looks beautiful in the fall and through the winter.
Ruby Muhly Grass grows in a mounded shape, up to a few feet wide.
If you live in the Denver area, you can see beautiful examples of Ruby Muhly Grass at the Denver Botanic Gardens. Zones 5-10.
Blue Mist Spirea
Caryopteris x clandonensis
Blue Mist Spirea is an easy-to-grow shrub that’s covered with blue flowers in late summer. It often blooms for up to 8 weeks during August and September.
This shrub is a pollinator MAGNET! It attracts a variety of bees and butterflies in late summer—when many other shrubs and perennials are done blooming. And bonus, deer and rabbits tend to skip it!
Use Blue Mist Spirea to add structural interest to your garden, as a border plant or in a hedge. It grows to about 3 to 4’ wide and tall. Zones 5-8.
Dwarf Rabbitbrush (aka, Baby Blue Rabbitbrush)
Ericameria (Chrysothamnus) nauseosus var. nauseosus
Dwarf rabbitbrush offers vibrant, late summer flowers that attract native bees and butterflies.
As the name suggests, dwarf rabbitbrush is a mini version of rabbitbrush. It grows up to 2′ tall and 3′ wide. It’s native to Colorado’s Front Range. It has dense, silver-blue foliage and keeps its shape well. It lights up with golden flowers in late summer and fall in Colorado, often from September to November.
Rabbitbrush can spread its seeds like a fairy godmother tossing pixie dust, so be prepared to pull some seedlings. This shrub benefits from a light shearing in the late fall or early spring to increase next season’s flowers. Zones 4-9.
Related topics that may interest you:
- Why bees and butterflies are like puppies and kittens
- 3 plants that struggle in western winters (what NOT to plant in your Colorado garden)
- Planting a perennial garden in Colorado? 5 counter-intuitive tips