The 5 percent rule

Vice President Dick Cheney has his “1 percent rule”; after a recent experience, I formulated my own “5 percent rule.” But while Cheney’s rule pertains to security threats, mine concerns questionable plants in the garden.

courtesy Edmund Taylor

Questionable plants are those that, for various reasons, aren’t reliable. They may be less hardy, particularly tricky to grow, very early- or late-blooming, or they may exhibit irregular flowering or coloring, among other issues. On the plus side, though, they’ll probably be plants you won’t find at big-box stores.

Reliability is certainly a very worthwhile trait. After all, when we go to the trouble of buying and planting something, we want to be confident that it will reward us by doing its thing for the garden. But having made the case for stalwarts, how about those questionables?

Ten years ago, I bought a 2-year-old seedling of the Yulan magnolia (Magnolia denudata) after seeing a 50-year-old specimen in full flower in late February. Species magnolias grown from seed rather than cuttings are very slow to flower, often taking eight to 12 years to produce any blooms. That was one strike against it. The second strike was that it’s a tree and will eventually take up considerable space. The third strike was that it’s one of the very earliest of all the spring bloomers, making it extra susceptible to frost or freeze injury. Temperatures below 30 degrees for more than a few hours will toast those blossoms.

So with all the reliable spring bloomers out there, why in the world would anyone do what I did? The answer, of course, is that when I first encountered that mature magnolia in full glory, I thought I’d never seen anything so overwhelmingly beautiful. Those thousands of crystalline, pure-white blossoms in the gray, winter landscape were as close to a celestial vision as I’m ever likely to come.

It’s now the 11th year since I made my purchase. I had a handful of blooms in 2005—just enough to whet my appetite. Last year my tree, now 30 feet tall, was covered in buds; but as they were expanding in February, very cold temperatures killed every one, and we saw not a single bloom. This winter the tree was again covered in buds; and as they started to crack, I nervously watched the forecast. Finally, the first bloom opened in the warm spell after the bitter February cold. Within two days, there were hundreds of elegant blossoms that glowed in the dusk as if lit from within. We enjoyed this spectacle for five days until the frigid temperatures returned and whisked it all away.

Was it worth all the effort and wait for such an ephemeral show that was cut short and may not repeat for several seasons? Absolutely! There are those special questionables that are simply worth the wait.

Every garden should include a few such plants, which add an extra dimension and give us something remarkable and unexpected. The trick is to pick ones that are exceptional enough to warrant their fickleness—and make sure you don’t end up with too many of them.

To this end, I’ve formulated the “5 percent rule”: Roughly 5 percent of every garden should be questionables to add that frisson that’s often lacking in conventional plantings. The converse, of course, is that the remaining 95 percent of your plants should be more or less reliable, depending on your personal failure threshold. But if your current garden is made up entirely of stalwarts, the next time you come across that special questionable, find a place for the patrician among the yeomen.

[Garden designer Edmund Taylor lives and gardens in the wilds of Madison County. He can be reached at swallowtailgardendesigns@hughes.net ]