15 Garden Plants That Can Become Weeds If Not Controlled

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Some garden plants can enhance the appearance of outdoor spaces, yield fresh fruit and vegetables, and attract beneficial insects and pollinators. That said, some plants can also grow out of hand if they are not kept in check. Aggressive in their growth, these plants will suck the water, sunlight, and nutrients away from other greens in your garden.

Here are 15 common garden plants that have the potential to become weeds if not controlled.

Mint

Mint has a nice, aromatic scent and tends to spread rapidly in gardens. Mint, if not controlled, will grow over an entire area and other plants will become choked out and impossible to manage. If you want to avoid mint turning into a weed, grow it in pots or keep on top of removing new growth.

Morning Glory

Morning Glories are annual vines that bloom all summer long with lovely flowers. Nonetheless, the rapid proliferation of these plants is also resulting in adverse effect. If left to their own devices, these vines can be aggressive and choke the life out of any plants you’ve placed in your yard. Pruning the plants regularly, and by removing seedlings of these will prevent morning glory from going insane.

Japanese Knotweed

Despite its dainty white flowers, Japanese knotweed is considered the most invasive plant in the world. This root system will immediately begin going to battle with your nearby garden beds, tearing up foundations and dominating native species. Japanese knotweed should be removed by excavation, so that the roots are taken out all together or using herbicides.

Blackberries

Photo Credit: Krzysztof Ziarnek, Kenraiz/Wikimedia Commons

Blackberry bushes make a nice addition to yards and provide tasty fruit. These can spread quickly due to runners underground and of course, are notoriously difficult to control. Removing root suckers and thinning young canes every year can prevent blackberries from becoming a weed problem.

Bamboo

Bamboo (which is actually a fast-growing perennial grass) helps to evoke an Asian-inspired exotic flair in the garden. But it also might be a great candidate for becoming a weed very soon with how aggressive it can grow. Like other varieties of bamboo, this type can quickly take over your yard by spreading through underground rhizomes. Instead, plant bamboo in containers or use barriers to hold it back.

English Ivy

a close up of a plant — Photo Credit: Pexels

English ivy is a common groundcover. It does well in shade and lends a sophisticated look to gardens. It is also an aggressive spreader, happily choking off other plants in its path. By pruning regularly and by pulling sprouts back in, English ivy’s weed status can be kept at bay.

Trumpet Vine

Trumpet vines are a pretty flowering plant that having bright coloured blossoms attracts humming birds. These are very fast growing vines that multiply through underground runners and can be quite invasive if not kept under control. Prune your trumpet vine regularly to keep growth in check and to remove suckers that can start new plants.

Sunflowers

Sunflowers, are known for their bright blooms. They are usually grown as annuals because some species have been found to self-seed and become a pest in the garden. Sunflowers will easily dominate your garden, so pick off the flower heads before they drop seed, and grow them in pots.

Strawberries

Photo Credit: Dietmar Rabich/Wikimedia Commons

While strawberries are a delicious and popular garden fruit, their runners can quickly take over an area meant for other plants. To prevent this, regularly thin out strawberries or plant them in containers.

Wisteria

Wisteria is a beautiful twining vine that will romantically blanket an entire garden nook. Yet other than that, they will grow voraciously and can be a challenge to control. It can become a tree, shrub and other plant killer left to its own device.

Yucca

A great landscaping plant that you can incorporate in your garden is the yucca. Once established, their sword-like leaves and deep roots make them difficult to remove. Yuccas should be divided regularly to discourage them from becoming weeds and seed pods can be removed to prevent their spread.

Lemon Balm

A ScienceDirect publication reports that lemon balm is a fragrant herb. It has many uses besides culinary ones. Left unchecked, it can become a rampant weed in your garden or jump the fence and take over adjacent plants. To keep lemon balm from taking over, plant it in a pot or contain its growth regularly.

Purple Loosestrife

A study by the National Institute of Health shows that purple loosestrife shows that purple loosestrife is a lovely wildflower that attracts bees and butterflies to your garden. But when left unchecked, it can turn invasive as a weed. A large root system enables it to spread across marshlands, outcompeting native plants.

Daylilies

Daylilies are known for their colorful flowers and low-maintenance growing conditions. They can also quickly spread and become invasive if not kept in check. One way to control this problem is by deadheading or pulling out clumps of daylilies on a regular basis, to keep chokers from spreading.

Creeping Charlie

Photo Credit: Jay Sturner/Wikimedia Commons

Sun-loving ground covers, creeping charlie, or ground ivy is a very common ground cover for shady locations. Although, due to its vigorous spread, this can become a weed if allowed. Maintaining consistent mowing or trimming of the creeping charlie will keep it in check and keep it from taking over your garden and suffocating other groundcover plants.

Disclaimer: This list is solely the author’s opinion based on research and publicly available information.