July 13th, 2012
The summer of 2012 has so far been brutal on some parts of the ornamental garden; the high temperatures and lack of rain here in Connecticut are challenging to fussy perennials and thirsty annuals. Isn’t there an easier way to have a pretty flower garden in the dog days of summer? You betcha! Stick with long-flowering, old-fashioned colorful stalwarts such as coneflower and phlox paniculata.
Tall garden phlox is different from her spring-blooming cousins: subulata, divaricata and stolonifera. This summer bloomer is considered the queen of the July and August perennial patch. Our grandmothers grew phlox and the hybridizers have had a field day with it since then. The flowers now vary from purple to red to orange and pale pink and through to pure white, and are often fragrant. The sizes range from a dwarf 12 inches to a statuesque four feet. Its strong stems remain upright even in the face of wind and rain, and it multiplies every year.
Every garden should contain at least a stand of ‘David’, the pure glowing white cultivar which won the Perennial Plant of the Year award in ’01. Or ‘Laura’, with her winsome white eye in a deep pink flower head. Or ‘Robert Poore’, a strong, regal purple.
Phlox is ridiculously easy to grow, requiring only sun, room for wingspread, and average moisture. It’ll flourish in any good compost-amended garden soil, but do it a favor and apply a helping of Plant-tone in spring. Phlox is simple to divide when the bounty overruns the boundaries; just plunge a spade in the ground and hoist up a chunk.
No plant is perfect, however; and there are several factors of which to be aware with phlox. Watch for and rogue out seedlings. A vigorous cross breeder, phlox will set seed with abandon, resulting eventually in stands of magenta flowers across the garden.
If you have Bambi in your neighborhood you’ll have to apply repellent regularly. Deer, which are attracted to the scent of the flowers, (just as are people), will devour phlox especially in the spring, when tender new growth emerges, and when in bud later in the season.
Powdery mildew is an occasional, unsightly fungal nuisance which starts on the lower leaves and works its way up the stems. It’s best counteracted by growing resistant cultivars, such as the ones mentioned above, and by judicious thinning of the stalks early in the season. Mildew needs stagnant air to flourish; thinning promotes ventilation and thereby thwarts disease. And be sure to practice good garden sanitation. This means cleaning up every last dropped leaf come autumn, and discarding, not composting, the spent plants.
A couple of other tips to growing glorious phlox. In June, whack off the top 1/3 of the plant. Doing so postphones bloom but doesn’t affect anything else. Unattended, phlox will burst into glorious color in July, but when delayed, bloom will occur 3 or 4 weeks later, still with the same full, colorful show. We need color in late August more than in July.
Remember to deadhead faithfully. As you gather armloads of flowers for your tall vases, (and I hope you will) clip off spent flower heads. This will keep the side shoots coming, giving you garden color well into September.
Phlox, that favorite of our forebears, needs to keep its rightful place in our hearts and our yards. Let’s welcome her back!