9 Flowers You Should Never Plant in Your Garden, According to Experts

Close up of wisteria flowers blooming in spring — Credit: Getty / Natalia Ganelin

Flowers fill homes and gardens with color, fragrance, and beauty. Plus, they are an important nectar source for essential pollinators like birds and bees. That said, there are some flowers you should never plant in your yard or garden. From toxic species to varieties known for their invasive nature, we're sharing the flowers experts urge against growing in your landscape.

Kathy Jentz, host of the GardenDC podcast and author of Groundcover Revolution
Jan Johnsen, landscape designer and author of Gardentopia: Design Basics for Creating Beautiful Outdoor Spaces

01 of 09

Japanese Honeysuckle

Even though Japanese honeysuckle (Lonicera japonica) is an attractive vine with eye-catching foliage and unique, elaborate blossoms, you don’t want this invasive plant in your yard. Japanese honeysuckle spreads from seeds and rhizomes and can rapidly climb trees, shrubs, and plants—sometimes to staggering heights. When climbing, it can tightly wind itself around other plants, eventually choking them and potentially killing the plant or tree. Japanese honeysuckle is especially an issue in the eastern half of the U.S., particularly in the southeast. If you're looking for a decorative vine to incorporate into your landscaping, try something non-invasive like cross vine.

02 of 09

Gooseneck Loosestrife

While there’s no denying that gooseneck loosestrife (Lysimachia clethroides) is a charming plant with sweet white flowers that resemble a goose's neck, it's also widely recognized as a troublesome invasive. "It looks great in bouquets, but it's quite aggressive in the garden. I learned that the hard way," says landscape designer and author Jan Johnsen.

03 of 09

Blue Violet

Viola sororia are native to eastern North America. — Billy_Fam / Getty Images

Ground cover plants have their uses. In shady areas where lawn grass may struggle to grow, a ground cover can give you a unified green appearance, and they're useful on slopes that are too steep to mow. Blue violets (Viola sororia) can make a lovely flowering ground cover but if they get loose in your grass lawn, they can be a nuisance. While harmless and nontoxic, violets can still be a lawn pest if you dislike small flowers interfering with your grass.

04 of 09

Lesser Celandine

Cheerful yellow flowers are the hallmark of lesser celandine (Ficaria verna), but this flower has a caveat. "One invasive flower I'd avoid planting is lesser celandine," says podcast host and author Kathy Jentz. "It is incredibly hard to remove and can quickly spread over a cultivated garden area." Sometimes called a "fig buttercup," lesser celandine has pleasant blossoms and shiny leaves. Despite its beauty, this flower rushes to out-compete many lawn or ground cover plants you try to grow. It spreads underground through small bulb-like tubers that spread even more when disturbed.

05 of 09

Wisteria

Long admired for its beauty as a vining plant, wisteria (Wisteria sinensis) looks beautiful when growing on architectural elements in the garden or around the home. But unfortunately, wisteria is considered an invasive plant and, if left unchecked, can harm trees. "I'm not a fan of either English ivy or Asian wisteria," says Jentz. "I have battled both for many years in my home garden, and they are difficult to control and eradicate once they have a toe-hold." She recommends looking for an alternative option, such as native American wisteria cultivars like 'Amethyst Falls' and other forms of ornamental ivy. "They are much slower growing and garden-friendly," says Jentz.

06 of 09

Belladonna

Belladonna, also known as deadly nightshade (Atropa belladonna), is a flowering shrub you won't want to include in your garden because it's extremely toxic. It’s not a plant you want in your garden or yard, as it's toxic even to the touch. Besides its toxicity, belladonna isn’t a particularly unique or attractive-looking shrub; the foliage, blossoms, and berries are all somewhat nondescript. There are better (and safer!) flowers to plant instead.

07 of 09

English Ivy

Ivy growing on wall — Colors Hunter / Chasseur de Couleurs / Getty Images

Climbing flowering vines can look great in the right spot. But English ivy (Hedera helix) is something to avoid. Not only are the leaves poisonous to humans and pets, but the vine itself is invasive and can spread disease to trees. If you really want a cover vine, there are more useful options than English ivy. "An idea for an English ivy substitute with a similar look is the native vine Virginia creeper," says Jentz. Virginia Creeper grows a thick cover, and the leaves turn a wonderful bright red in the autumn.

08 of 09

Foxglove

Foxglove (Digitalis purpurea) is a beautiful flower with downward-pointing bell-like blossoms reminiscent of columbine. Some gardeners use foxglove in borders or as a colorful showpiece. But all the beauty notwithstanding, you might want to avoid planting foxglove because it's toxic to humans and pets. Simply touching the plant can cause skin irritation, while ingestion or absorption can cause health issues. As an alternative, snapdragons have a very similar appearance to foxglove.

09 of 09

Monkshood

Although undeniably beautiful, monkshood (Aconitum napellus) is an extremely toxic plant. Due to its toxicity, it's not a good choice for a home garden where children and pets can easily access it. Snapdragons are a non-toxic option that gives the same visual effect as monkshood.