Companion planting involves strategically placing different plant species near each other to create a mutually beneficial growing environment, enhancing garden health and visual appeal. For cannas, known for their bold foliage and vibrant blooms, thoughtful companion planting can create a more robust and aesthetically pleasing display.
Why Companion Plant with Cannas
Companion planting with cannas offers several distinct advantages for the garden ecosystem. One primary benefit is the enhancement of visual harmony, as complementary colors, textures, and forms can create striking garden compositions. Beyond aesthetics, this practice contributes to improved garden health. Certain companions deter common pests, while others attract beneficial insects such as pollinators, aiding in the overall vitality of the garden.
Companion planting also supports better soil health. Some plants help with nitrogen fixation, enriching the soil, while others act as groundcovers, suppressing weeds and retaining soil moisture around the cannas. Maximizing garden space is another practical advantage, as diverse plant heights and growth habits can fill various layers, creating a fuller, more layered look.
Choosing Canna Companion Plants
Selecting appropriate companion plants for cannas requires considering several environmental and aesthetic factors to ensure compatibility. Both cannas and their companions thrive in similar conditions, primarily requiring full sun. Cannas flourish in rich, moist, well-draining soil, so companion plants should share these moisture and nutrient preferences.
The size and growth habit of companion plants are also important considerations. Taller canna varieties are often best placed at the back of a garden bed, with shorter, bushier plants filling in the mid-ground. Smaller canna cultivars are well-suited for containers or the front of borders, where they can be paired with trailing plants. Aesthetic harmony is achieved by selecting plants with contrasting foliage textures or complementary bloom colors to enhance the canna’s dramatic presence. Choosing companions with bloom times that precede, coincide with, or extend beyond the canna’s long flowering season ensures continuous garden interest.
Recommended Canna Companion Plants
Many plants can beautifully complement cannas, adding layers of texture, color, and ecological benefits to a garden design.
Annuals
- Marigolds: Deter pests like nematodes, aphids, and whiteflies with their strong scent, adding vibrant orange and yellow hues.
- Zinnias: Offer a wide array of vibrant colors that complement canna blooms and fill garden spaces.
- Coleus: Provides richly colored foliage, offering striking contrast to canna leaves and thriving in similar warm conditions.
- Lantana: A robust annual providing continuous blooms, attracting pollinators, and known for pest resistance.
Perennials
- Salvias: Feature spiky flowers that contrast with canna’s broad leaves and prefer sunny conditions.
- Dahlias: Offer diverse forms and colors, complementing or contrasting with cannas for a lush effect.
- Coneflowers (Echinacea) and Yarrow (Achillea): Extend blooming interest, attract pollinators, and offer different floral forms.
- Hibiscus: Adds a tropical feel with large, exotic flowers, attracting bees, butterflies, and hummingbirds.
Elephant ears (Colocasia) boast large, bold leaves that amplify the tropical aesthetic of cannas and share similar requirements. Sweet potato vine (Ipomoea batatas) provides a beautiful trailing element, with varieties offering chartreuse, purple, or bronze foliage that spills over edges and contrasts with the upright canna stems. Ornamental grasses, such as purple fountain grass, provide a fine, feathery texture that offers a soft contrast to the bold structure and broad leaves of cannas, adding movement and visual interest.
Planting and Care Tips
Canna rhizomes should be planted horizontally about 2 to 4 inches deep, with any visible buds facing upwards. While cannas multiply quickly, a spacing of 12 to 18 inches allows for good air circulation and growth, though closer spacing can create a fuller appearance in rich soil.
Consistent moisture is crucial for cannas and their companions, as cannas are thirsty plants that prefer continuously moist, but not waterlogged, soil. Regular watering, especially during dry spells, supports vigorous growth and abundant blooms for the entire grouping. Deadheading spent canna flowers encourages the plant to produce more blooms throughout the season. If canna leaves become damaged or dull, cutting them back by half or to the ground can stimulate new, fresh foliage and flower production.
Plants to Avoid Near Cannas
While many plants make suitable companions, some should be avoided near cannas due to differing needs or competitive growth habits. Plants requiring dry soil are incompatible with cannas, which prefer consistently moist environments. Pairing plants with significantly different water requirements can lead to one plant suffering.
Aggressive growers that spread rapidly can outcompete cannas for nutrients and space, hindering their development. For example, some mint varieties are known for their invasive growth habits and can quickly overtake a garden bed. Additionally, avoid planting shorter sun-loving plants directly beneath tall cannas, as the cannas’ large leaves can cast dense shade, depriving the smaller plants of necessary sunlight.