Hardy down to -30 degrees F, purple phlox are adored by butterflies, bumblebees, hummingbird moths, and other pollinators. Phlox is an exceptional perennial for many climates, and purple varieties are truly stunning. Vervain ( Verbena stricta ) If you’re looking for a North American native perennial with purple flowers, vervain is an excellent choice. The tall purple perennial flowers produced on these plants are real standouts in the garden.
Topping out at 4 to 5 feet in height, sun-loving vervain is among the most underused purple-flowering perennials. Plants are somewhat difficult to find in the nursery trade, but it’s easy to start from seed. The deer don’t bother it, and many of our native bees find its nectar delicious. The airy blooms of vervain are tall and stately in the landscape. German bearded iris ( Iris germanica ) German bearded iris come in a rainbow of colors, but my favorite hue by far is violet. Thankfully, there are many varieties to fulfill your desire to add purple flowering perennials to your garden. Iris thrive in full to partial sun, and they’re tough as nails. Don’t bury the rhizomes too deeply, though, or they rot. Of the many deer-resistant purple perennials available, German iris are among the easiest to grow.
Fully hardy down to -40 degrees F and reaching 2 to 3 feet in height, iris are early spring bloomers with a carefree nature. Though bearded iris are common, you can’t beat them for their resilience and ease of care. Bear’s breeches ( Acanthus mollis ) If you’re looking for a large perennial with purple flowers, bear’s breeches has you covered. Big, bold, spine-covered leaves are topped with 3-foot-tall spires of hooded flowers every summer. Thriving in full sun, bear’s breeches’s blooms last for months. Winter hardy down to -20 degrees F, give this purple perennial tons of room in the garden. And with all those spines, the deer and rabbits leave it alone. No plant is bolder in the garden than bear’s breeches. The big spiny leaves and hooded blooms are amazing. carmichaelli ) This plant is a real treat for gardeners looking to add purple perennials that bloom in the fall. My monkshood is the latest blooming flower in my landscape. Tall spires of flowers don’t open until very late summer and last well into autumn. Give this plant full sun and the flowers stand tall. Hardy to -40 degrees F, monkshood tops out at 3 to 4 feet in height. Be warned, however, that all parts of this plant are poisonous, so wash your hands thoroughly after working with it. This trait also makes monkshood deer-resistant, which is certainly an added bonus. Monkshood is among the latest flowering perennials in the garden, often in bloom well beyond fall’s first frost. Tatarian aster ( Aster tataricus ) Of all the tall purple perennials out there, Tatarian aster is my hands-down favorite. A magnet for migrating monarchs, this late-blooming perennial with purple flowers stands a whopping 6 feet tall! It’s smothered with clusters of small, pale purple flowers that are relished by many different pollinators at a time when little else is blooming in the landscape. Thriving in full sun and requiring no staking for support, Tatarian aster is hardy to -40 degrees F. Though the deer don’t eat it in my garden, I have heard from other gardeners who find their plants nibbled by deer from time to time. Pollinators love, love, love the late blooms of Tatarian asters. False indigo ( Baptisia australis ) False indigo is an exceptional early-blooming perennial.
I enjoy watching the chubby bumblebees pop open the lidded blooms each spring. They’re among the only bees heavy enough to open the flowers and pollinate them. False indigo is another plant on the list of purple flowering perennials the deer don’t eat, which is certainly a nice bonus.
The straight species of false indigo produces spikes of purple-blue flowers, but there are other varieties that bloom in shades of yellow, burgundy, and white. Growing to 3 feet in height in sunny spots and with a winter hardiness down to -40 degrees F, false indigo doesn’t have a particularly long bloom time, but the foliage itself is quite lovely.