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Phlox paniculata; a Perennial Favorite

As the summer progresses and the dramatic early perennials such as Oriental Poppies, Peonies, Allium and Irises start to wane, it’s a relief to know that, very soon, the summer phlox will start to put on their fireworks display. This perennial makes a great impact in the dog days of summer especially when several different varieties of paniculata are planted together. While the humidity of July and August might cause some varieties to develop mildew, it is now possible to select varieties that have been bred specifically to be mildew resistant.

Phlox paniculata David is a white variety that is mildew proof and consistently outperforms all other Phlox. Compared to colored varieties, it is more dense and lush, better at tolerating partial shade and recovers more quickly from transplanting shock. Recently, breeders have been using David as a parent plant to develop colored phlox that are mildew resistant. It will be interesting to see if these varieties will also possess the other desirable qualities of white David.

There are many varieties of Phlox to choose from. Start by selecting colors that work well with the overall theme of the garden. Then, narrow the choice to those that are mildew resistant and only after that exercise, if the desired color scheme is still unfilled, opt for the traditional varieties.

Plant Phlox in an open location where they will receive a lot of air circulation to help prevent mildew. Also, ensure that water sprinkler jets, both above ground and underground types, are aimed away from the Phlox. Very often, even when summers are dry, Phlox will develop mildew simply from showering in too much water. A drip hose is the ideal water source for this perennial.

Among the traditional varieties, those with a contrasting colored eye such as Bright Eyes or those with a bi-colored petal such as Natascha, tend to be mildew resistant. David’s Lavender, shown above, is a new mildew resistant variety. This jumbo, slightly fragrant, lilac-colored bloom has a pink eye and will grow almost three feet tall. However, while most summer Phlox are hardy to zone 4, David’s Lavender is only hardy to zone 5.

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Reader Comments (1)

I love Phlox of all varieties, but seem to have had bad luck with them over the years. A large clump of hot magenta phlox, for example, that I made the mistake of dividing: The bunch I gave away looks great in a neighbour's garden -- mine didn't make it.

Recently, I purchased a new and unusual cultivar, P. 'Natural Feelings' for its promised long blooming period and fragrance. So far, it's just getting started. The bloom does seem to last, but it's such an odd-looking critter that it doesn't make much of an impact... at least, not in my garden. TBD. Perhaps I should just stick to the basics and get myself some P. 'David'.

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