We started our SSAW journal with an article saying farewell to the ranunculus and we are closing the season saying goodbye to the dahlia. In my fields, I grow these two crops in rotation so this feels like a proper send off for the 2020 growing season. In many ways these two plants are grown as a cut flower crop in very similar ways in the UK, they are both perennial plants in the warmer climes of their countries of origin (Mexico and Iran respectively), but are often grown as annuals here in the UK as they are able to survive periods of dormancy which means they can be lifted from the ground and stored during the winter.
Whilst some flowers immediately feel tropical, many of the flowers that seem naturalised in the famous British ‘cottage garden’ (a model often used as a basis for planting plans by UK market flower farms and thus grown as standard) originate from much further afield. The existence of these flowers in Britain is often the result of exploratory expeditions afforded by colonialist ideologies. Dahlias (or Cocoxochitl perhaps we should we say) for example, which soon became a garden mainstay were first introduced to the UK in 1804 by Lady Holland, a well known society figure who sent back seeds from the Royal Botanic Gardens in Madrid, where in turn they had been brought from Mexico by the conquistadors. Acknowledging the true history of plants and recognising that there is often a bloody past behind the beauty is essential in decolonising the garden. (You can read more about this here).
Cared for by flower farmers for 12 months of the year, dahlias are a revealing example of the time spent producing each and every British grown bloom - the many hours over many months nurturing, watering, feeding, deadheading and weeding before it is cut and conditioned and then eventually arranged. Labour, it is important to consider and is often overlooked when analysing the financial value assigned by the free market:
Cheap produce usually means that someone is being exploited and in most cases something too (local water sources, biodiversity etc.). Fair prices must include fair wages, a hugely important aspect of the true cost of seasonal produce.
Back in April, I took out the tubers from where they were stored, gave them a last check over for any sign of rot, removed any unhealthy ones, divided any excessively large ones and potted them up in compost. (Lulu’s keen to try compost mixed with equal parts sand and mole hills as a potting mix for next year. The sand works well at holding in the moisture and mole hills are free and therefore reduce the amount of compost you have to use - there’s nothing more satisfying than making good use of a nuisance!) I then left them in the warmth of the polytunnel to sprout, watering sparingly and doing my best to protect them from slugs, waiting for the last frosts to pass to plant them out.
In the first week of June, I planted them into beds I had fed with well rotted manure. Ideally, dahlias prefer free-draining, lighter soils, where they are better able to survive the winter, but they do grow on heavier soils like mine it just means you are more likely to need to improve the soils by adding organic matter or sowing green manure as a nitrogen fix (dahlias thrive off it), and to have to lift the tender tubers at the end of autumn to prevent damage if clay gets waterlogged during winter. All dahlias like a sunny site with plenty of space between them, accepted horticultural wisdom suggests planting at least 60cm apart, 10 to 15cm deep. (Jess and Lulu would be the first to admit that their plants were too close together which resulted in weaker blooms. This is all part of the learning process , trialing different techniques and understanding different plants needs.)
By July when the first flowers began to show, I had pinched them out at 30cm, staked them with strong, heavy duty netting, begun to feed them roughly every ten days with seaweed and watered deeply once a week. Regular deadheading back to the leaf joint encouraged the plants to produce more blooms, and from then until now the dahlia beds have been a riot of colour of all shapes and sizes.
Apparently, there are 42 recognised species and nearly 57,000 registered cultivars with 100 new added every year. I grew over 50 different types, a mixture of the different groups of dahlia, with distinctive flower characteristics Single, Pompon, Decorative, Collarette, Anemone, Cactus and Waterlily, to get a real breadth of shapes, styles and shades, but there are many more I would like to trial next year. Normally, I would grow mainly for events for which the short life span of a dahlia is no problem, selling them as bunches this year meant that I favoured those with smaller heads, tighter petals and better longevity. Interestingly these also seemed to dry best, something we are trying for the first time this year. Even those that did not do so well for cutting were wonderful for the insects they attracted. Evidently the vibrancy of their colour is a result of the fact that they do not attract pollinators through scent.
Jess and Lulu took theirs out last week and next week I will follow after them, cutting down the stems and composting them, digging up the tubers, freeing them from as much soil as possible and storing them in crates surrounded by straw or sand or other insulating material in a cool, dry shed away from direct sunlight. (I wont split the tubers at this point as it could create damage which could become vulnerable to rotting so I will wait until Spring). Now is the perfect time to make notes about your season and which Dahlias you would like to grow next year. Specialist UK Dahlia growers Just Dahlias and Witthy Pitts are excellent sites to scour.
SOME NEW FAVOURITES FOR 2020 HAVE BEEN:
Dahlia ‘Gallery Art Deco’
Dahlia ‘Caribbean Fantasy’
Dahlia ‘Take Off’
Dahlia ‘Great Silence’
Dahlia ‘Happy Single Kiss’