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Astoria, Intensia phlox can thrive for months
By Norman Winter
Central Mississippi Research & Extension Center
When spring arrives and gardeners start trying to jazz up the landscape with color, many will look for long-lasting color so they won't have to change out plant material a couple of times before fall. If that is your goal, too, I would like to heartily recommend the Astoria and Intensia series of phlox.
These are not your grandmother's phlox. Breeding that no doubt incorporated grandma's favorite varieties has given us these two relatively new series that offer blooming performance all summer. They have native Phlox drummondii in their breeding.
We normally think of that native phlox as an annual, with its bloom peaking in summer and then tapering off rather quickly. This is not the case with the Astoria and Intensia series.
The Astoria will reach about 24 inches tall, and it has a mounding habit, so space them 18 to 24 inches apart. The Intensia series is closer to 14 inches tall, although it grows slightly taller in the South. Both varieties have a penchant for blooming.
The Astoria and Intensia phlox bloom in a riotous display all summer and well into fall -- even in winter in milder climates. Never before have we had such a display of phlox.
If you love the woodland phlox, also called Louisiana phlox (Phlox divaricata) in the South, and lament when its season is over, rejoice because you can pick up those blues or silvers with the Astoria series.
The Astoria lavender really looks like the native woodland phlox but with larger flowers and a full season of bloom. You will find 10 colors in 2009 -- one of which is sure to fit your palette. I love the Astoria Hot Pink and the Astoria Magenta.
The Intensia series boasts a half-dozen colors. My favorite here is the Intensia Neon Pink and Intensia Cabernet.
When spring finally arrives you will want to plant your phlox in fertile, well-drained soil giving them plenty of sun for best blooming. They are certainly tolerant of a little afternoon shade or filtered light. After planting, apply a good layer of mulch to conserve moisture and deter weed competition.
Both the Astoria and Intensia series are low maintenance, requiring no deadheading. In our Mississippi trials, we have given the phlox a light trimming in late summer to have them at their peak performance for our October Fall Flower and Garden Fest. You'll notice that both series have a delightful fragrance and will do their part feeding nectar-hungry bees and butterflies.
By all means, also use them in mixed containers. They aren't quite tall enough for the thriller plant but will be unbeatable in the filler role. They also excel in hanging baskets.
In the landscape, your choices are almost mindboggling. They will work with just about any other flower partner you choose from salvias to grasses to the rugged Diamond Frost euphorbia.
You'll have a lot of choices this spring. Why not try Astoria or Intensia phlox?