Some are garden thugs; others are maintenance hogs or one-hit wonders. Don’t bother planting these shrubs.
Pruning a privet hedge is like painting the Golden Gate Bridge—once you’re done you just have to start over again. At least it seems that way. Privet (Ligustrum spp.) grows so quickly that it has to be pruned four to five times a year if you want that neat and clean look. It does provide privacy, but it doesn’t have much beauty. And, if you fall behind on the trimming, it will quickly look unkempt. Choose something that doesn’t require so much maintenance.
It’s a relative of poison ivy. Need I say more? Not everyone is allergic to staghorn sumac (Rhus typhina), but those who are will experience intense itching that’s only temporarily relieved by scalding water (not recommended, by the way). Then there are the watery blisters that spread the itchiness if they’re opened by scratching or bathing. Now, why would you want to bring THAT into your yard? Did I mention staghorn sumac spreads easily by its roots and forms thickets? Ugh.
Japanese barberry (Berberis thunbergii) sneers at neglect and doesn’t even bat an eye at drought. To top it off, there are some really colorful cultivars out there in hues of chartreuse and burgundy. But the shrubs are thorny (good for barriers, bad for bare skin). And the bright red or orange berries are eaten by birds, then deposited elsewhere. Trouble is, Japanese barberry can dominate a landscape, crowding out native plants, especially in the Northeast, Great Lakes area, and parts of the Northwest. There are better options without the baggage.
It’s got show-stopping fall color—the red and yellow really catch the eye even from a distance—and it’s simple to grow. However, burning bush (Euonymus alatus) grows fast (reaching up to 15 feet in height), so it typically needs regular pruning where space is lacking. And, it has become invasive in woodlands in the East, Midwest, and South, thanks to seeds dispersed by birds. It can’t even be legally sold in Massachusetts or New Hampshire.
Bush honeysuckle (Lonicera spp.) has fragrant flowers and bright red berries. Sounds good, right? But it’s a nasty pest that spreads by roots and seeds. It pops up everywhere and out-competes native vegetation simply because it is so un-demanding when it comes to conditions. Sun, shade, wet, dry—to bush honeysuckle, it’s all good. And, if you grow one, it’s all bad (for you).
It’s a tough shrub with bright orange or red berries. It can be trained into a topiary, too. However, pyracantha is a problem in California, Texas, and parts of the Deep South, where it has invasive tendencies. Elsewhere, it’s just a hassle to deal with, thanks to thorny branches and a tendency of “dieback,” meaning you have to deal with the thorns as you remove the dead wood.
Butterfly bush (Buddleja davidii) has its virtues. After all, it attracts butterflies—that can’t be bad. And it’s drought tolerant and has pretty flowers. In Zone 5, however, it dies back to the roots in winter, so you have to cut it back to the ground in spring (more work) and hope it still flowers. And, in certain areas, such as the Pacific Northwest and much of the East, butterfly bush is considered invasive. If you do grow one, look for a sterile cultivar.
Like so many other invasives, buckthorn (Rhamnus cathartica) was brought in to this country as an ornamental. It’s now considered a noxious weed because it out-competes native vegetation, forming an impenetrable barrier and degrading wildlife habitats. Its thorny nature is also no fun to work with, so good luck taking a pruning saw to it. While you’re getting rid of all the buckthorn,
Everyone loves this golden harbinger of spring when it’s in bloom—for about 15 minutes in early spring. Seriously, the show is about a week long and then you have a green blob the rest of the growing season. Make that a green blob constantly in need of a haircut, because forsythia tends to look unruly if it doesn’t get a regular snip. More maintenance and fewer flowers (if you wait too long to prune it) is not a recipe for a great shrub when there are so many better candidates.
This weedy shrub has sharp thorns, which makes it a pain to deal with. Literally. But its real threat is the fact that autumn olive (Elaeagnus umbellata) is easily spread by birds and then ends up out-competing other plants because it is so adaptable, even making its own nitrogen. It’s actually banned in a number of states.