Description
Tree Dahlia Pink (Dahlia imperialis) features large, single lilac-pink flowers scattered along tall, arching bamboo-like stems. These towering giants are a rarity in the Dahlia world, making a grand statement from summer through winter. Their stately architectural form allows them to swiftly reach towering heights, with graceful flowers cascading downwards, creating a stunning visual wherever they are planted.
Tree Dahlias flourish in warm climates with mild winters and abundant sunlight. For optimal growth, plant them in spring after the last frost has passed, selecting well-drained soil enriched with organic matter. Opt for a sunny, sheltered location, ideally against a garden wall or fence to shield them from strong winds that can harm their tall, bamboo-like stems. Alternatively, they thrive when grown in large tubs or pots, offering flexibility in size control while showcasing their stunning blooms. Ideal for garden beds, borders, or cut flower arrangements, Dahlias enhance gardens with elegance and vibrant colours effortlessly.
Tree Dahlias, thrive best in well-drained soil that is rich in organic matter. They prefer soil that is loose, fertile, and slightly acidic to neutral (pH 6.5 to 7.0). Amending heavy clay soils with compost or well-aged manure helps improve drainage and provides essential nutrients for healthy growth. Additionally, ensuring the soil is loose and friable allows the tubers to develop properly and facilitates good root growth.
When planting Tree Dahlias in pots, choose a large container with a diameter of at least 18 inches (45 cm) to accommodate their tall growth and root development. Use a well-draining potting mix enriched with organic matter; adding compost or aged manure can provide essential nutrients. Place the tuber in the centre of the pot, ensuring the crown (where the stems emerge) is just below the soil surface. Position the pot in a sunny location receiving 6-8 hours of sunlight daily, shielding it from strong winds that can damage the delicate stems. Keep the soil evenly moist but not waterlogged, watering thoroughly when the top inch of soil feels dry, particularly in hot weather. Tall stems may require staking to support their height; loosely secure the stems to the stake as they grow. Apply a balanced fertiliser every 3-4 weeks during the growing season to promote healthy growth and flowering, following the manufacturer’s instructions. Optionally, apply a thin layer of mulch on the potting mix to retain moisture and regulate soil temperature. Regularly remove dead or damaged stems and spent flowers to encourage continuous blooming, and prune back overly vigorous growth as needed to maintain the plant’s shape. In colder climates, protect the roots from freezing temperatures by moving the pot to a sheltered location or insulating around the pot. Reduce watering in winter while ensuring the soil does not completely dry out.
Planting Tree Dahlias in garden beds is similar to planting them in pots. Use well-drained, organic-rich soil, and space the tubers 3-4 feet (90-120 cm) apart to accommodate their tall growth, ensuring the crown is just below the surface. Support the plants with individual stakes or a trellis system. Water newly planted Tree Dahlias thoroughly to settle the soil around the roots. Keep the soil evenly moist, especially during dry periods, and water thoroughly when the top inch of soil feels dry, but avoid waterlogging to prevent root rot. Apply a balanced fertiliser every 3-4 weeks during the growing season to promote healthy growth and flowering, using a formulation suitable for flowering plants. Mulch with shredded bark, straw, or compost to retain moisture, suppress weeds, and regulate soil temperature, keeping it a few inches away from the stems to prevent rotting. Regularly remove spent flowers to encourage continuous blooming. In colder climates, cut back the stems after the first frost and cover the base with a thick layer of mulch to protect the roots from freezing temperatures. If unexpected frost occurs, cover the plants with frost cloths or blankets. Reduce watering during winter, ensuring the soil does not completely dry out. In warmer climates, Tree Dahlias can remain in the ground year-round.
Tree Dahlias are not typically divided like other dahlia varieties that grow from tubers. They are usually propagated through stem cuttings or seeds rather than the division of tubers. Therefore, they do not require dividing regularly. However, if you find that your Tree Dahlia has become very large and overcrowded, or if you want to propagate more plants, you can consider dividing the tubers. This is usually done in early spring before new growth begins or in winter after flowering has finished.
Tree Dahlias can grow very tall, reaching heights of 10-20 feet (3-6 metres) or more. Cutting them back helps to control their size and prevent them from becoming too sprawling or top-heavy. Pruning stimulates new growth and helps maintain a healthy, bushy plant. Removing old, dead, or diseased growth improves the overall appearance of the plant and encourages better air circulation.
In colder climates, wait until after the first frost when the foliage begins to yellow and die back naturally. This indicates that the plant is entering dormancy. In warmer climates where Tree Dahlias may remain evergreen or semi-evergreen, early spring is a good time to cut back old growth before new growth emerges. Cut back all dead, yellowed, or diseased stems to the base of the plant using sharp, clean pruning shears. Trim back healthy stems to a desirable height, typically leaving about 6-12 inches (15-30 cm) above ground level. This helps maintain a tidy appearance and encourages new growth from the base. After cutting back, consider applying a layer of mulch around the base of the plant to help retain moisture and protect the tubers during dormancy.
This practice is particularly advantageous in regions with harsh winters, providing essential protection for the tubers against severe frost. Store them in a cool, dry location like a basement or garage, using slightly damp peat moss or sand. Replant them in spring after the last frost for optimal growth.
Monitor for common pests such as aphids and spider mites, and treat infestations promptly with appropriate organic or chemical controls. Ensure good air circulation around the plants to reduce the risk of fungal diseases.
Important Note: While we aim to provide accurate representations of our products, factors such as climate, natural variations, or manufacturing updates can impact the exact appearance of each variety. The images usually feature mature specimens, while the supplied stock contains dormant tubers that will develop over time. Please use the images as a general guide, considering that the pack may also include the same colour and tuber variety.
Supplied as a dormant tuber.