Chrysanthemums, companions can compete with October’s nature
Posted: Tuesday, October 9, 2012 8:00 pm
By: By Jimmy Williams
October is a glorious month. There’s little need for a garden. Just take a drive down any rural road and there are pictures on every hand. Nowhere else in the world is there such a plethora of autumn wildflowers as in the eastern United States. “A pictur’ that no painter has the colorin’ to mock,” as the Hoosier poet, James Whitcomb Riley, so aptly put it.
But human nature — and more to the point, a gardener’s nature — being what it is, we want our gardens to excel those of Mother Nature. It ain’t easy in October.
But we go down trying. There are some (not too many) “garden” plants — some native, some exotic — that can compete with the roadsides this month and into next. And they’re not all chrysanthemums.
Speaking of which, however, let us address them first. The cushion mums sold by the thousands this time of year are not bad plants, but many will prove to be temporary, for one season only. Planted in fall, they have no time to send out roots away from the original form of the container and are apt to heave out of the ground with severe freezes.
Better are the so-called Korean mums, which are indeed natives of Korea. These grow in a looser fashion and will prove to be much more winter hardy. Alas, they are seldom seen in nurseries in fall.
A great fall bloomer is physotegia, or obedient plant. The straight species is pale purple, with spikes of flowers atop three-foot stems in autumn. These would be wonderful companions to mums, but, unfortunately, obedient plant is absolutely not obedient. It is so invasive at the root it will bully out anything in sight. I grow mine in a wild area where invasiveness is not a problem. Never, but never, plant it in polite company. A white form is not as aggressive. Among very few fall flowering woody plants is Caryopteris x clandonensis, or blue mist shrub. It works well in a perennial border with fall flowering herbaceous plants. The blue flowers go great with almost any color of mum, from white, to yellow and bronze.
The variety with the richest blue color is Dark Knight. We have a couple of these at our driveway, one of them alongside the pink of a muhly grass. The blue shining through the pink gauze of the grass will make you want to garden more ardently.
Caryopteris does well treated as a cut-back, that is, pruned to six inches or so in spring. It will then make up into a three-foot shrub before fall. Flowering starts in July, then pauses a bit. I shear it off at that time, and by September it is covered again with that rich blue. There are yellow-leaved forms, too. The yellow of the leaves makes a smashing combo with the blue flowers. The best of these is Sunshine Blue.
Caryopteris is very drought resistant and adapts to poor soil. What more could you ask? Well, you could wish for it to be longer lived. It has a habit of petering out after five years or so. Plants are, however, inexpensive, so it is well worth the cost for that amount of life, particularly when you consider the long flowering each of those years.
Butterfly bushes never grabbed me, maybe because I could never seem to grow them well. The straggly habit and gaunt winter framework turned me off.
Now along come several compact varieties with a more shapely and smaller growth habit. Blue Chip was the first one on the scene and there are now several others. Butterfly bushes, including the new ones, will start flowering in early summer and continue right on up until frost.
I have a new specimen of Flutterby Blue, that has been going well since I set it out in July. The description said it would grow to two feet or so. Butterfly bushes are cut-back shrubs and should, like caryopteris, be whacked back to 6 inches or so in spring after danger of frost.
From Poor Willie’s Almanack: Break out of that mum box before it is too late.
Jimmy Williams is the garden writer for The Paris Post-Intelligencer, where he can be contacted on Mondays at (731) 642-1162.
Published in The Messenger 10.09.12
Jimmy Williams, The Garden Path