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If you dream of a vibrant, low-maintenance landscape that returns beautifully year after year, you probably opt for a mix of several perennial plants. While these attractive, popular plants promise effortless charm, they often come with hidden headaches, from attracting pests and diseases to demanding specific conditions to flourish.
To help you avoid making a mistake in your garden, we spoke to a plant expert to identify seven common perennials that are far more trouble than they’re worth. Before you head to the nursery, read on to discover which problem plants to skip this season, the specific maintenance nightmares they cause, and alternative plants that will look great without all the hard work.
1. Alpine Delphinium (Delphinium elatum)
The magical alpine delphinium is most gardeners’ favorite perennial plant, says Marina Prokaten, plant expert at the plant identification and care app Plantum. These tall-stemmed plants are covered with gorgeous bell-shaped flowers that come in an array of colors, including blue, pink, white, purple, or cream. However, they are unreliable and finicky, and therefore challenging to care for in any garden. “They frequently require support to stay upright; often get affected by powdery mildew and slugs; and tend to decline in hot, humid summer weather,” explains Prokaten. Delphiniums also require full sun and soil that drains very well.
Grow this instead: Doubtful Knight’s-Spur (Consolida ajacis)
2. Peony (Paeonia officinalis)
Peonies are breathtaking plants, boasting gorgeous pink or red flowers that usually appear in late spring, says Prokaten. “Peonies aren’t that difficult to grow, but they do need upkeep,” she explains. “Their large, heavy blooms tend to collapse after rain, so they usually need sturdy support cages.” These are among high-maintenance plants, requiring full sun to flower but balanced with afternoon shade, well-draining soil, consistent moisture without becoming waterlogged, and enough space to grow.
Peonies tend to be susceptible to diseases like Botrytis and Phytophthora blight, and some sap-sucking insects can damage the plants. “Their flowering period is also relatively short,” says Prokaten. They need a period of cold dormancy to blossom. Finally, it is very difficult to transplant peonies once they are established.
Grow this instead: French Rose (Rosa gallica)
3. Red Azalea (Rhododendron simsii)
Azaleas are beautiful flowering shrubs known for their leathery green leaves and showy, ruffled flowers in vibrant shades of pink, white, and magenta. Unfortunately, they’re also famously unforgiving for the average plant lover, says Prokaten. “They require highly acidic soil, pure rainwater, and because of their shallow root systems, are quick to die if the soil gets too dry or waterlogged,” she says. Also, their delicate buds are easily damaged by harsh winter drafts and intense afternoon sun. Red azalea is native to East Asia and is more tender in the West, so be careful when selecting plants like these for your garden.
Grow this instead: Bigleaf Hydrangea (Hydrangea macrophylla)
4. Bearded Iris (Iris germanica)
Bearded irises are admired for their unique sword-like leaves and striking, multi-layered petals in a rainbow of colors with soft, fuzzy centers. However, achieving those picture-perfect blooms requires a bit of precision, warns Prokaten. “Their thick roots must sit right on the topsoil to get enough light, as burying them even slightly will cause the plant to stop blooming and rot,” explains Prokaten. “They’re also vulnerable to bacterial and fungal diseases during rainy weather and need to be dug up and divided every few years.” Finally, overcrowding is another common issue as these plants mature.
Grow this instead: Orange Daylily (Hemerocallis fulva)
5. Tall Garden Phlox (Phlox paniculata)
This classic flower contributes a lot of color to gardens that have already started losing it as other perennials shed their blossoms, says Prokaten. They are known for bringing color and fragrance to garden borders, available in red, white, blue, pink and magenta shades. This species also attracts pollinators like butterflies and hummingbirds to the yard. However, they are hard to grow due to their susceptibility to mildew and rot diseases.
Grow this instead: Candy Cloud Blue Mounding Phlox (Phlox hybrida)
6. Dahlia (Dahlia x hybrida)
Dahlias come in a rainbow of vivid colors and diverse blooms that can look like everything from delicate peonies to perfectly round pompoms, says Prokaten. However, they are high maintenance, as they are susceptible to both extreme heat and cold temperatures. “Hybrid dahlias in particular are quite labor-intensive; they can’t survive cold winters, meaning you have to dig up, disinfect, and carefully store their tubers every single fall,” explains Prokaten. “Throughout the growing season, they also demand constant watering and heavy fertilizing, as well as staking to prevent wind damage.”
Grow this instead: Purple Coneflower (Echinacea purpurea)
7. Gardenia (Gardenia jasminoides)
Gardenias are a stunning garden favorite, loved for their bright white flowers and incredible, sweet fragrance, says Prokaten. “However, these tropical plants are quite fussy and can drop their buds overnight from a cold draft or a lack of light,” she explains. “They also require a pronounced difference between daytime and nighttime temperatures, and are highly prone to pests like spider mites.” You may also notice their leaves yellowing, which can be addressed by spreading fertilizer with iron.
Grow this instead: Mock Orange (Philadelphus coronarius)
The post 7 Pretty but Problematic Perennials You’ll Regret Adding to Your Garden appeared first on Bob Vila.