If you don’t want to spend years picking off invasive plant shoots or struggling to remove aggressive or invasive plants, it’s best to avoid these eight finicky perennials in your backyard.
Fortunately, there are great alternatives that will look just as good without any of the added hassle.
Perennials are tough to avoid in a small backyard
The saying right plant, right place really applies to small backyards because you don’t want a fast-growing perennial to get out of control and dominate your planting scheme.
It’s worth thinking twice before choosing any of these fast-growing plants for a small space.
1. Wisteria
Wisteria roots can spread quickly anywhere
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The stunning wisteria vine is known for its delicate, colorful flowers that droop downward. They are especially popular when planted near pergolas or arches to create an ethereal living roof.
Unfortunately, wisteria vines are also incredibly aggressive and can quickly take over small gardens if given space. Wisteria roots spread quickly and have been known to suffocate nearby plants. Roots and vines can also easily damage nearby structures such as walls or fences.
One of the most common types of wisteria, Chinese wisteria (Wisteria sinensis), is considered invasive in many states across the United States – especially in the eastern states.
What to plant instead: Try farming Hydrangea petularis (Climbing hydrangea, available at Nature Hills) is also great for climbing structures but grows much slower.
2. Lily of the valley
Lily of the valley will spread quickly underground
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Councils of convalaria It is a popular woodland plant ideal for shade gardens. It produces long stems interspersed with bell-shaped flowers that symbolize spring renewal, happiness, and motherhood.
Although lily of the valley flowers are beautiful, they are not ideal for small gardens. This plant spreads through roots beneath the soil, and under the right conditions it spreads quickly to completely overtake flower beds. Their underground spread also makes them difficult to remove, and you’ll likely notice new stems emerging season after season in the spring.
If you want to try growing lily of the valley in a small yard, it is suitable for gardening as its spread can be contained in a container.
What to plant instead: You can plant snowdrops (Galanthus nivalis) which features similar flowers without the aggressive growth habit. You can buy snowdrop bulbs and plants on Amazon.
3. Crocodile
Crocosmia crocosmiiflora (Montbretia) is one of the most invasive Crocosmia species.
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Native to sunny South Africa, crocosmia features fiery yellow, orange and red flowers. These colorful pollutants not only benefit your backyard, but also benefit butterflies and birds. These flowers are known to attract hummingbirds and help grow local wildlife populations.
But for those with small backyards, these benefits come at a cost. Many species are considered invasive due to their rapid growth and rapid spread. Crocosmia Crocosmiflora (Montbretia) is one of the worst offenders, but there are many other species that are best kept out of small spaces.
the University of Florida He recommends planting named varieties that are less susceptible to invasion than regular varieties.
What to plant instead: Try farming Lobelia cardinalis (Cardinal Flower), available at Nature Hills. It has similar fiery flowers and the ability to attract hummingbirds.
4. Common periwinkle
Common periwinkle is considered an invasive plant in many areas of the United States
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Commonly used as a ground cover plant in difficult areas. Finca is a minor They are appreciated for their ability to quickly fill a space and produce gorgeous blooms, even in shady locations. Unfortunately, this rapid spread is also its biggest downfall.
Due to the plant’s popularity and wide availability, common periwinkle is grown in many parts of the Northern Hemisphere. Thanks to their rapid spread and ability to grow almost anywhere, they have eluded home garden cultivation, taking over local areas and threatening native species.
What to plant instead: Wild blue phlox (Phlox divaricata) It enjoys similar conditions and bears flowers of the same colour, making it a great alternative to periwinkle.
5. Jasmine in sweet autumn
Although clematis have a wonderful scent, they can choke out other plants in a small backyard
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Take a look at our list of fragrant flowers and you’re likely to spot sweet fall clematis. This vine produces carpets of delicate flowers in summer and fall that fill gardens with a sweet, intoxicating scent.
This fast-growing flowering vine can reach over 10 feet tall when mature. But that’s not the only thing that makes it unsuitable for small gardens. Clematis It also suffocates nearby plants and spreads via seed to new places in your garden and beyond.
What to plant instead: Other types of jasmine also grow vigorously and can become very tall, but they are not considered as invasive Clematis Choose one of these, or choose one more suitable for small gardens, such as Boulevard® Alaina clematis, available at Nature Hills. Alternatively, you can grow jasmine vines for a similarly sweet scent.
6. Butterfly bush
Buddleja can grow too quickly to fit in a small yard
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Buddleia davidii It is a garden favorite perennial with bright flowers in many colors across different cultivars. Purple is the most popular color, especially when those flowers are covered in the butterflies they are known to attract.
Despite its benefits in attracting pollinators, experts recommend avoiding butterfly bush altogether, especially in small gardens. Not only is the plant large, but the seeds of the fast-growing shrub spread throughout the garden and into native habitats, replacing native plants.
What to plant instead: Another perennial plant known to attract butterflies is Echinacea (Coneflower). The flowers come in a range of colors, allowing you to choose the perfect variety for your space and the butterflies in your area. You can buy echinacea seeds on Amazon.
7. Lamb’s ear
Lamb’s ear will self-spread to other areas of your garden
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I’ll be the first to admit that I found a fluffy sheep’s ear (Byzantine Staches) Completely irresistible. The soft foliage and pleasant gray color complement many other perennials and the compact size is perfect for bed borders.
However, lamb’s ear stems can develop roots and spread along beds if exposed to soil. Moreover, they also self-spread their seeds in other parts of your garden. Although it may not be officially declared invasive in many areas, its rapid spread is still not ideal for small gardens.
What to plant instead: Mexican bush sage (Salvia leucantha), available at Nature Hills, is my favorite alternative that can be used to fill space or trimmed to keep compact in small gardens. The purple flowers have a similarly delicate texture and are great for attracting pollinators.
8. Obedient plant
Physostegia virginiana can be difficult to remove once it has spread
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Physostigia virginiana It is a native of North America and has an interesting common name – obedient plant. This name comes from the stems that will stay in place if moved or blown. Its other common name, false dragon’s head, originates from its resemblance to snapdragon flowers.
The stems may be obedient, but when it comes to spreading, this plant is not. Physostigia virginiana It spreads aggressively and is incredibly difficult to remove – not an ideal choice for those with limited space.
What to plant instead: Fortunately, if you like the look of this native species, you can simply choose another cultivar with a less harmful spread. ‘Miss Manners’ (available from Nature Hills) is a great choice with a limited spread and compact size, ideal for small gardens.
9. Bamboo
Bamboo’s fast-growing nature can pose a problem in a small yard
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Due to its fast-growing nature, bamboo is often chosen by homeowners as a quick way to create a garden screen for patios or decks, but this feature can also be its main problem as it can quickly get out of control, especially in a small yard.
“Bamboo brings height, fills in corners and creates screens,” says garden expert Anne Swithinbank. “They are evergreen, skeletal, rustle in the breeze, and when well maintained, can generally be an asset. You can try to control their growth by pruning and tidying up clumps annually in spring or summer.
“You can also prevent the spread of new and existing bamboo plants by installing a physical barrier,” Anne adds. “Line a trench at least 24 inches deep with paving slabs, corrugated iron, or root barrier fabric suitable for bamboo. Let the barrier stand proud in the ground to prevent roots from creeping up.
If you’re ready to plant one in your small garden, phyllostachys varieties are best, because their spread is more gradual.
What to plant instead: Instead of looking for an alternative, you can simply change how you plant and contain your plant in a pot to prevent the bamboo from spreading and taking over your small garden. However, they can become pot-limiting, so you will need to consider replanting them every two to five years in the spring.
Having trained at Kew Gardens in London and worked in the garden department’s nurseries and as a greenhouse supervisor at RHS Wisley, Anne has worked as a freelance horticulturist since 1986. Anne writes for UK gardening enthusiasts magazine and was a panelist on BBC Radio 4’s Gardeners’ Question Time For 27 years.
common questions
What is the most invasive perennial?
Invasive perennials are specific to the region and climate in which they live. Some are more aggressive in warm areas, while others spread quickly regardless of conditions.
To identify invasive perennials in your area, check with your local extension service for their advice.
When planning a small garden, choosing the right flowers is an essential part of the design process. Beautiful, flower-filled borders are always an attractive option, but it pays to do your research and avoid fussy perennials that can quickly take up a small space due to their fast-growing or invasive nature.
The good news is that there are plenty of alternatives to consider instead, or you can also consider growing them in pots to restrict their growth.
