This is not any old dahlia – it’s the emperor of dahlias. Dahlia Imperialis, commonly known as the imperial dahlia, tree dahlia or giant dahlia is native to Mexico and Central America where it can grow to 3m tall. It can be shorter in temperate climates and in the UK it requires a sunny and hot summer combined with the absence of early frosts before it deigns to flower around late October to November. As a cut flower dahlias stubbornly refuse to open their buds in water. I was lucky and picked this flower stem just as the buds were opening and the day before a frost was forecast. If it flowers outside the blooms hang down and show their faces from the top of the stems. Growing this plant is one of those challenges that excite gardeners as, unless you are in a vey favoured location, it is a lottery whether it will ever enjoy the right conditions to flower.

Tags: Blossom, plants