I think fall is often the most overlooked and under-appreciated time in the garden. Maybe it's like downhill skiing in April. People figure the ski season is over and it's time to pull out your hiking boots. Yet, true "powder hounds" know that here in the Rockies, the biggest, deepest powder days arrive with water-laden April storms. Well, the analogy is the same for the fall landscape; some of our most incredible and showy ornamentals are at their best after summer has passed when many gardeners have hung up their trowel.
Read on to learn our top reasons to love late-blooming perennials, and see a list of our favorite perennial varieties for a beautiful garden in fall.
Summer Rains and Fall-Blooming Native Plants
Fall is a glorious time in the Intermountain West, Great Plains, and the Southwestern US. Many of our native plant species are responsive to the mid-summer rains that bring much needed moisture in July and August (affectionately known as the "monsoon season," when cloud bursts dump rain by the inch). Native plants respond to the monsoons with a burst of fall color, some of which are actually re-blooming after their late spring flush.
Plants To Provide Fall Garden Habitat
These fall blooming native plants have always been a focus of High Country Gardens perennial selection. Not only do these plants delight us with their brilliant flowers, but they are integral to the habitat garden.
Late-season blooming plants provide:
Precious nectar and pollen to migrating monarchs and hummingbirds migrating south to their winter habitats in Mexico/southern most Arizona & New Mexico.
Seeds and fruits for songbirds.
Nectar and pollen for butterflies, native bees, honey bees and bumblebees so necessary to build winter food reserves.
While the spring garden is full of smaller, compact flowering perennials and bulbs, the fall garden is the realm of big perennials and ornamental grasses that have been growing all summer before coming into flower.
Late-blooming Agastache Ava provides plenty of nectar for hummingbirds, summer through fall.
A to Z Perennial Highlights for the Fall Garden
Garden mums and ornamental cabbage or kale have become commonplace at big box stores, but they are of no value to pollinators. If you're going to plant a fall blooming mum, look for heirloom, single flowered varieties which are nectar-rich. Take a walk on the wild side and put your funds and labor into more sustainable perennials, which will last for many seasons to come.
Commonly known as Poppy Mallow or Wine Cups, Callirhoe involucrata is a native wildflower that decorates the garden with a summer-long display of bright magenta-pink flowers. A sprawling grower, Callirhoe involucrata's long branches spread out across the ground to create a colorful mat of flowers and foliage. Drought resistant perennial plant (xeric).
Perovskia atriplicifolia Blue Spires (Blue Spires Russian Sage) is the best large growing Russian Sage selection blooming with dark blue flower spikes appearing in mid-summer. Thought to be a hybrid of two species, this plant has amazing vigor and blooms for many months.
Salvia sylvestris ‘May Night’ (May Night Sage) blooms prolifically with deep purple-blue flowers. It is an outstanding perennial with excellent cold hardiness, vigor, and tolerance of heavy clay soils. Blooming in late spring with a profusion of flower spikes, it reblooms later in the summer when deadheaded.