Beautiful but Deadly
It may come as a surprise to know that you probably have a dangerous plant or two in your garden. Some are obvious, popping up and invading your entire landscape. Others are more discreet, relying on birds, wind, and unknowing humans to spread their progeny throughout woodland areas where they infiltrate and displace natural flora and fauna. Some wait for the curious pet to take a bite before unleashing their life-threatening assault. Before you prepare another hole for your next plant, get to know some of the biggest bullies on the botanical block.
One of the most common landscape shrubs throughout the country, non-native Burning Bush (Euonymus alatus) is prized for its fiery red fall color and the ability to perform in both sun and shade. With the exception of wet poorly drained soil, burning bush is highly tolerant of most growing conditions, which is its biggest strength when it comes to edging out competition in natural areas beyond the cultivated landscape. Burning bush develops small fruits favored by birds in autumn who deposit the seeds along their flight path.
It may look pretty scrambling up a tree trunk or along a brick wall, but beware. English Ivy (Hedera helix) has an insidious way of choking out its host. Often used as a fast-spreading groundcover, it suppresses all other vegetation to form a dense carpet that’s inhospitable to wildlife. When grown as a vine, it will swallow entire trees and shrubs, blocking sunlight and resulting in slow death of the host plant. If it doesn’t kill it, its weight alone will almost certainly break limbs and/or weaken woody plants, making them more susceptible to disease. Native to Europe and Western Asia, English ivy produces tiny black berries that are favored and spread by birds.
Also called Bradford pear, the Callery pear was the go-to flowering ornamental tree in home landscapes across the country since the 1950s. The fact that it couldn’t self-pollinate made it even more attractive because it meant the tree would never produce messy fruits. The problem occurred when horticulturists focused on improving the tree’s weak branch structure by breeding stronger cultivars. Unfortunately, these new cultivars were capable of inter-breeding and the result was an invasion of fruit-producing Callery pear trees whose fruits were appealing to birds. Consequently, Callery pear saplings dominate the edges of forests and open fields where they nudge out native vegetation.
The best way to ensure you have a life-long supply of mint is to plant it directly in the ground. In which case, you will have nothing but mint growing there in a very short time. Mint spreads quickly by underground runners that grow just beneath the soil’s surface, producing new plants along the way. With time, mint forms a dense underground rope-like carpet that’s near impossible to eradicate. Leaving behind just a small piece of the root will undoubtedly allow the plant to proliferate. To prevent mint from overtaking your lawn and garden, grow it in containers and harvest sprigs as needed.
Related: 15 Plants Never to Grow in Your Yard
Found on many “must-have” plant lists for pollinator gardens, unfortunately the butterfly bush (Buddleia davidii) isn’t host to any caterpillars in the United States. Native to Asia, it has no natural predators to keep it in check. Dust-like seeds float easily on the wind, landing in fields and along roadsides where they crowd out beneficial plants. The plant is so invasive that many states on the east and west coasts have declared the butterfly bush a noxious weed.
Harbingers of spring, daffodils adorn landscapes across the country. But pet lovers should be concerned, especially if you have a dog that likes to dig or cat that enjoys sampling the flora. While the toxin is predominately in the bulbs, all parts of the plant are poisonous and can cause gastrointestinal issues, excessive drooling, and in the worst cases, convulsions and heart problems.
Don’t let the heavenly name fool you, all parts of Angels Trumpet, or Brugmansia, are poisonous to people and animals. Native to South America, it’s commonly grown in containers in cooler climates and prized for highly fragrant, sometimes 20-inch long flowers that are a hummingbird favorite. While ingestion of any of its part is dangerous, accidental poisoning occurs when plant sap enters the bloodstream and is most common among gardeners who’ve handled the plant then rubbed their eyes or eaten food. If you must grow Angels Trumpet, wear gloves when pruning and be diligent about cleaning up fallen leaves.
A hummingbird magnet, trumpet vine is the Incredible Hulk of aggressive woody perennial vines that, when given plenty of warmth and moisture, can take over an entire landscape in a single season. In arid climates, trumpet vine tends to be better behaved but is best located away from foundations, sidewalks, and driveways where their roots can inflict some serious damage. Grow trumpet vine on a strong trellis away from trees and shrubs that it could potentially strangle.
The ominous name is enough to raise a red flag. Death camas are often mistaken for wild onion and are native to North America, commonly found across the Plains and western regions where they pose a risk to livestock and grazing animals. Among the first plants to emerge in spring, the grass-like leaves grow from a bulb resembling an onion. Small bunches of dainty six-petaled white flowers appear in late spring. All parts of the plant are poisonous.
Castor Bean Plant
Large star-shaped leaves of castor bean plants add an exotic flare to gardens and containers where they grow to heights of six feet or more. Unfortunately, all parts of the plant are poisonous, especially the seeds that develop inside highly ornamental spined capsules that explode when mature. The seeds are released as projectiles all over the garden where they may be of interest to curious pets and small children. To prevent this, remove the seed capsules when they appear. We’re not saying you can’t grow castor bean plant, just be very careful.
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