There are so many things to say about Dahlia selecting and growing. It’s not just the luscious gorgeous-ness of the flower nor the vibrancy of available colours nor the elegant detail of the flower shapes and sizes not even it’s excellence as a cutting material or indeed how it holds it’s own in a mixed border all of these elements combined with the timing and length of flowering make it one of those must grow plants in my view.
Now I know they are not always hardy and can require a great deal of tlc over the winter but if one choses cultivars carefully and takes a few overwintering precautions one can potentially cut down the workload by keeping them in the ground overwinter. Cold and wet are the main enemies and there will always be some risk of loss in our sometimes frozen and wet climate. Precautions such as well gritted planting holes, well drained planting areas, thick mulches to the crown, protected locations and protection in the emerging weeks. In fact those I leave in ground tend to emerge much later than those started on pots. That said there is also some risk in dry storage even in the most clement of circumstances. Last winter I lost 2 boxes of tubers, about 8 plants, sitting next to another 3 boxes which survived quite happily, all in a dry, frost free environment. No rhyme or reason. One can speculate their demise but in the end I accepted the risk.
Several years ago I grew a packet of Bishop’s Babies seeds from Sarah Raven. Almost all grew (15 or 20 plants) and almost all were rather lovely, as a hybridiser of Iris I have learned to be rather ruthless with seedlings and weed out, read – compost, all but the best plants, chosen for flower shape and colour, vigour and disease resistance. These are my selection criteria others may have different ones. I weeded out all but 4 plants and they have been planted on my allotment plot for around 5 years now. I don’t lift them in winter, I cut them back and mulch them with compost, about 4-6 inches, after the first frosts. Then I wait until the following May/June when I hope to see new life emerging and so far they have, increasing in size each year.
Last year saw some additons in the form of Cafe au Lait, Hillcrest Royal, American Dawn along with some gifted beauties from friends and this year I have a hugely expanded collection with a further 40 cultivars as well as a packet of PomPom seeds for seedlings. The plan is to treat them much the same as before, cutting them back after the frosts, mulching the crowns and then covering the whole area back up with a mid weight landscape fabric to keep the weeds and local diggers (foxes, cats) at bay. In April 2018 the covers will come off and I shall start the weeding and staking process keeping an eye out for tiny shoots telling me all is well.
April and May are ‘hovering’ months, watching for frosts in the main, in the shsed is a bag full of fleece and old net curtains which can be employed should inclement weather threaten my emerging plants. Slimey predators will be discouraged by nematodes in spring as well as the increasing froggy population. Once May is up then they’ll be fed with multipurpose feed (blood, fish and bone) monthly until they start to flower then it’s onto foliar feeds with a high pottasium count until September when they won’t be pushed or cut anymore but allowed to build their tubers for the following year.
Well, it’s a plan at least, we shall see how we weather this winter!
More to come on choosing cultivars and finding nurseries….