The summer bulb Dahlia, originally from Mexico, is making a triumphant return to our gardens and parks after shedding its ‘dated image.’ The speed at which new cultivars are crossbred and propagated is propelling the assortment into significant growth. It’s not always easy to maintain a stable catalogue due to growers bidding farewell to cultivars for various reasons. The positive side? There’s more development in flower shape and colour than in other bulb crops. Discover a beautiful, broad assortment in the Verver Export catalogue.
Crossbreeding and propagation
When different dahlias are planted together, there’s a chance these cultivars will crossbreed. The seed often differs from the bulb in the ground, leading to spontaneous hybridization when the seed is sown.
Breeders work more systematically, crossing flowers with the expectation of achieving a different colour or the same shape and colour but with better leaf placement and sturdier stems. After crossing, the new seed pod is protected to prevent insects from depositing different pollen spontaneously.
The dried seed is sown in early spring, with the first flowers appearing after approximately 120 days. These may not be as large as those from a mature bulb, but they’re sufficient to assess if the new cross is worthy of selection. To compare with tulip breeding, where it takes four to five years for the first results of the cross to be visible!
Tijmen Verver personally visits breeders annually to evaluate new crosses. Quick coordination with breeders and growers is essential, as these new gems can be included in the catalogue much faster than many other bulb crops.
Cuttings for (rapid) propagation
Tubers are ‘imposed’ in containers in early spring in a warm room with high humidity. Soon the first green ‘sprouts’ form around the old flowering stalk of the tuber. When these sprouts are about 7 cm long, they are cut from the tuber and planted in sand with cutting powder. We call this cutting dahlias. Because part of the plant is taken, the new tuber is identical to the tuber from which the cutting was taken. The cuttings are hardened off in cold greenhouses before being planted outside in the field in mid-May.
On the land, the planted cuttings grow into large, deliverable dahlia bulbs in a single season. This is much faster than with other flower bulbs and bulbs, where not every planted flower bulb develops into a deliverable (guaranteed blooming) size.
Showstopper until first frost
Dahlias are true showstoppers in public spaces, colouring beds and containers much longer than other summer bloomers, lasting until the first frost. That’s precisely why Verver Export’s ready-made summer concepts always feature dahlias. In fact, these concepts are often built around a specific dahlia cultivar. Supporting annual plants that bloom early, fill beautifully in the summer, but let the dahlia take centre stage in midsummer.
Especially for public green planners who want to provide food for bees and butterflies until late summer, a special line (Alfa-Zulu) of single-flowered, open-hearted dahlias has been included in the Verver Export catalogue. These bulbs are also organically grown. In combination with butterfly-friendly annual plants, a ready-made concept, Bees & Butterflies, is also included in the catalogue.
Explore more about the extensive range of dahlia cultivars (over 200 different) and concepts at www.ververexport.com. Be inspired to incorporate this fantastic summer bloomer into your creations in gardens, public borders, and parks.
