In March, of last year, I wrote a post about growing dahlias. In it, I challenged myself to overcome my habit of buying tubers that never actually made contact with a growing medium, never mind the light of day. My intention was to replace the flowers I had unquestioningly bought on a whim, whilst working, with something more cost effective and home-produced. Why - I reasoned - would I want to buy blooms flown in from foreign fields that would last a few days at most when - for a fraction of the price - I could invest in a tuber that would supply a succession of flowers for several months of the year? I had intended to report back in late summer, heralded by a fanfare of trumpets, because when you've announced to quite a lot of people that you intend to do something, you really have to live up to it don't you? And I did live up to it but never got round to telling anyone. The plants were a bit late going from pot to border but flowered their little hearts out for a couple of months before an unseasonably early frost blackened the foliage at the beginning of October. So, inspired by last years efforts, I grew even more this year and it is now that they are really coming into their own.
The photo above was taken last year, in early August, and the dahlia shown is the cactus-flowered 'Nuit D'Ete'. I planted the dahlias in a mixed bed with roses and other plants but found they overwhelmed their allotted space quite quickly. Also, not being able to reach each plant from all sides meant that routine tasks, like feeding and dead-heading, were difficult. This year they are in a bed of their own - with three feet between plants - and this makes them much easier to manage. I started the tubers off in pots of compost in my tiny greenhouse at the end of April, keeping a careful eye on the weather forecast for night-time frosts. Some tubers are bigger than others so you need an assortment of pot sizes; the tuber needs to sit comfortably inside and still be able to fit compost around it and under it. My smallest tubers will fit into 2 litre pots but I pot the biggest into 5 litre ones. Also the tubers will grow bigger each season. They only need to start into growth in the pots and then they can be planted out once the risk of frost has passed at the end of May. So if you clean your pots straight after planting the dahlias out they are all ready to start again next year.
When I plant them out, I hammer in a stout stake - prior to planting so I don't damage the tuber - and mix plenty of compost with the soil as I firm it back in around the plant. Dahlias grow best with plenty of moisture at their roots but enjoy having their heads in the sun. I find the best thing for fastening them to the stake is the cut off leg of a pair of tights! The stretch in them allows the plant to move a little but without the sharp jerks caused when you fasten with string that can cause brittle dahlia stems to snap. Water them really well once a week in dry weather and I also feed about every 10 days with dilute manure water. Dead-heading helps to keep the flowers coming and I also nip out the two small buds - either side of the main one - to encourage bigger flowers. You can leave your dahlias in the ground over winter if you mulch them well but last winters frost and snow turned several of my tubers into a soggy mush. One of the ones I lost was this Fuschiana, pictured above, so this year they're all coming up after the first frost kills the foliage. Sarah Raven has a good chapter on dahlias - including growing, managing and storing over the winter - in her book Grow Your Own Cut Flowers. There's also a very useful chapter on sweet peas, another favourite of mine.
Colourwise, dahlias come in a wide range of hues although I believe someone has yet to breed a blue one. Their palette ranges from the soft and muted to the truly retina-scorching. Some varieties are bi-coloured, most often with white, while others have subtle variations of colour like this Black Narcissus, shown above. It is quite a dark dahlia yet full sunshine illuminates all its red tones. I am particularly fond of these almost-black varieties as they combine so well with other colours and prevent the paler shades from looking too insipid.
In size, they range from the tiniest miniature ball - with a diameter of just two inches - to those with blooms the size of a dinner plate. In fact, they are often described as just that - 'dinner-plate dahlias! Rip City - above - is one of my favourites. It has flowers of six inches and more across with gorgeous velvety petals of deepest maroon black. I struggled to find this one but I've noticed that Peter Nyssen Ltd will be stocking them next year and you can order a catalogue online. Hide your bank cards whilst perusing it, though, as all their prices are so reasonable the temptation to buy is - almost - irresistable! I have one called Lavender Perfection which has the hugest of blooms. Sometimes, I find that it may take a couple of initial flowers before the plant establishes its true shape and so the two samples I've had so far of this variety have been an odd shape. Fingers crossed for an improvement with the next few!
Sadly, sometimes they are not what you ordered/bought. This one is supposed to be Pontiac but is much more like Geerlings Jubilee from the same catalogue page (NOT Peter Nyssen)! I think you'll agree that it's very lovely though, especially against the shadowy background? Not too much of a loss there, then. Also on the minus side, dahlias have no scent as such, only a strange peppery smell but with all that amazing shape, colour and an abundance of blooms, who's to notice?
