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Summer phlox is a cherished perennial
By Norman Winter
Central Mississippi Research & Extension Center
Gardeners across the country cherish phlox, but it is one of dozens of plants that get passed over because it is typically not in bloom when it’s shopping time.
The phlox I am referring to is called summer phlox or garden phlox, and it is known botanically as Phlox paniculata. This phlox likes fertile, organic-rich beds with good drainage. I have seen phlox perform well in full sun, but I think a little shade in midafternoon makes a happier plant. Be sure to apply a good layer of mulch after planting.
There are more than 100 varieties of phlox available. While daily commuting to work a few years ago, I remember watching a planting of a deep purple garden phlox. These bloomed profusely from the end of May through the first frost. Encourage prolonged blooming by removing dead blooms and keeping the plants well watered.
At 3 to 4 feet tall, most garden phlox will look great planted to the rear of a perennial garden. You may need to provide some support to keep taller selections from falling over with their large blooms.
The variety David is a Perennial Plant of the Year and stands 36 to 40 inches tall. The glossy leaves are thin with bristly hairs on the margins. The pristine white, fragrant flower panicles are 6 to 9 inches long and 6 to 8 inches wide. David has a long bloom period during the summer and performs well in hardiness zones 4 to 9. One of its most outstanding attributes is its resistance to powdery mildew.
John Fanick is a Texas Super Star winner that has quickly caught on across the country. It reaches 36 inches in height, producing large heads of light pink flowers that have a darker eye. The plants exhibit great tolerance to fungal diseases.
A newer series to look for is the Peacock phlox with varieties Neon Purple, Purple Bicolor, Lilac and White. These are much shorter and offer disease tolerance and heat performance.
You’ll notice your phlox has another outstanding trait. Visiting butterflies and hummingbirds relish its sweet nectar.
Give yourself plenty of room to really create a dazzling display of phlox. Make your beds large enough to plant in informal drifts. Combine with other summer perennials like coreopsis, daisies, rudbeckias and salvias. By combining with these other perennials, you may not have to give taller varieties support, or if you do, it will be hidden.
Phlox that have been established for a couple of years can be propagated easily by root cuttings, stem cuttings or divisions. Clump division simply requires the separation of crowns within a clump. Division is done in spring or early fall. Root cuttings are best done after dormancy in the fall.
If you are looking for a plant that will return year after year, and offers fragrance, color and long-season bloom, there is no better choice than perennial summer phlox. It will not be blooming when you shop, but choosing a healthy green plant will give you a green thumb.