Can Someone Please Invent This Plant?
June 30th, 2020
There’s usually at least one suitable plant for any planting situation.
Evergreens can thin out like this in shade.
But I have nothing to tell the guy who emailed me looking for an evergreen he can use to give dense privacy in the shade of his mature trees.
Jim said he had tried interspersing ‘Green Giant’ arborvitae (an excellent plant) but found they lost their denseness under the canopy of his 60- to 70-foot-tall maples.
He wanted to know if there was another option for something that would give year-round dense screening in the woodland shade and filtered light – something that’s also fast-growing and resistant to deer.
“Is there any such evergreen?” he asked.
Not that I know of. If you do, let us both know. Or get to work breeding something because you’ll make a lot of money.
I suspect many people run into this dilemma. I can think of a few suggestions, but none that are ideal.
Back in the good old days, I’d have recommended hemlocks. These natives with the soft, flat needles aren’t particular deer favorites, they do pretty well in shade, and they stay fairly dense, too.
Woolly adelgids have infested this hemlock.
But twenty-something years ago, a bug called woolly adelgid came along to devastate the species. The problem has leveled out in recent years, but adelgids still pose enough of a threat that there’s a good chance they’ll find hemlocks and either thin them out from their chlorophyll-sucking damage (which undoes their screening benefit) or kill them outright.
Breeders at the U.S. Agricultural Research Service have managed to come up with a new cross between the Southern native Carolina hemlock and the Chinese hemlock that’s resistant to adelgids. However, the variety, named Traveler, isn’t in production yet, is at least years away from being on the market, and might be borderline winter-hardy in central Pennsylvania.
Upright yews are tough, dense, cold-hardy, and reasonably shade-tolerant, but deer love them.
Upright Japanese plum yews? Deer don’t care for them, but they’re so columnar in habit that you’d need a ton of them three to four feet apart to do any kind of screening.
Jim’s ‘Green Giant’ attempt was a good one because deer don’t like that form of western arborvitae nearly as much as our native eastern ones like the popular ‘Emerald Green’ variety. I’ve seen them do OK in part-day shade, but as Jim found, they really don’t do well in deeper shade.
A big part of the problem is that most conifers (pines, spruce, firs, etc.) are full-sun plants in their native environments. They tend to colonize open meadows and hillsides and don’t compete well as under-story plants when bigger deciduous trees go up and above them.
