Pippa’s PLOT
Pippa Blenkinsop, a budding flower grower and Period Living’s Style Editor, shares her passion for growing dahlias on her village allotment
For me dahlias conjure ...
happy memories of visiting village produce shows around the Cotswolds, with the finest stems proudly displayed in green florist vases encapsulating a lifetime’s passion. A couple of summers ago, to my delight, I stumbled across the National Dahlia Collection in Penzance while holidaying in Cornwall - it was a joyous moment and a true visual feast, with row upon row of dahlias as far as the eye could see. Making my way through the vast sea of colour, I was like a child in a sweet shop, mesmerised by the huge variety of shades and sculptural forms; this is when I fell in love with dahlias. Flowering from late June to the first autumn frosts, they are great for cutting and for bringing late summer colour to my plot, plus are guaranteed to make me smile.
From dainty single and...
star dahlias, to the dazzling decorative varieties with their giant dinner plate blooms of copious flat petals, there really is a dahlia for all tastes. The wonderfully retro and perfectly spherical ball and pompon dahlias, with their spirally arranged florets, make me marvel at what nature is capable of, but my personal favourites are the cacti-types, with their multiple narrow, pointed petals that curve backwards. While Dahlia ‘Preference’ is a particular favourite, for me, the pleasure lies in growing a variety, which look great together in vases or in the cutting bed.
For my first foray...
into dahlia growing, I chose the Cafe au Lait and William Morris collections from Sarah Raven. Offering a variety of different types of dahlia in a complementary palette, they were a good introduction. With blooms as big as my head, ‘Cafe au Lait’, like other giant decorative dahlias, is a flamboyant show-stopper in a border, however I found that even when staked the flowers tended to droop and snap under their own weight and were far too big for cutting. While I have some giant varieties, such as ‘Islander’ and ‘Penhill Dark Monarch’, this year I have focused on growing dahlias with smaller blooms, such as the cactus and waterlily varieties, as well as some pompons – I’m fond of ‘Little Robert’ (pictured bottom right), and singles, too, all bound by my favourite palette of pinks, oranges and peaches. As I love variety, this year I bought just single tubers of each type, but many retailers offer a discount on multiples. I am particularly excited about two new varieties I am trying: ‘Honka Fragile’, a star dahlia, and ‘Fancy Pants’, a star/collarette. Typically, I got carried away and, following a great year last year (see left the class of 2020), I have decided to grow double the dahlias!
To grow dahlias...
in April, pot up the tubers into five-litre pots (approx dia.22cm), filling them up to their necks with potting compost; they are then watered and left in the greenhouse. Growth rates will vary, but you should see shoots within five weeks. Dahlias are tuberous perennials, which grow best in warm, moist, free-draining soil and are frost tender, so must be kept under cover and well watered. As they grow they can be brought outside on sunny days to acclimatise, but should be taken in at night and not planted out until the risk of frost has passed. Having had so much rain this May, I only just managed to plant out my dahlias before the arrival of June; in two W1xl3.5m timber-edged beds I planted 17 dahlias, arranging them in height order and spaced around 45cm apart.
Dahlias can grow up to...
1.5m tall so will need support, such as bamboo stakes or metal rings – these need to be put in place when the plants are still small. Once the dahlias are 30cm tall, the shoots can be pinched out to encourage a bushier plant. When the dahlias are flowering I deadhead them almost daily to encourage new blooms, but it can be tricky knowing spent buds from new. The key is in the shape - new ones are round, spent are usually pointed. Dahlias can flower right up to December, but once the frost comes they are over. You can leave dahlias in the ground over winter if they are in a sheltered position with good drainage, but as the allotment is exposed, my dad and I tend to not take the risk and so lift the tubers. They are cut back, dug out, cleaned and any damage removed. They are then put to bed in a cool, dry place, until the following spring.
NOTES...
Dahlias can be grown from seed, but I have found that they haven’t turned out to be the colour I expected, while the tubers have. The cacti dahlias I grew from seed had very short stems and weren’t ideal for cutting.
Before planting tubers, check their condition and cut out any rot or damage. They should be firm, not dried out and shrivelled.
Dahlias are hungry plants that like being kept moist; digging plenty of well-rotted manure or organic matter into the bed before planting will keep them happy and will help the ground to retain moisture.
Cut dahlias in the morning or evening. Snip above the first leaf joint, or for longer stems, cut right back to a main upright, but be prepared to sacrifice unopened buds.
When lifting tubers be sure to label as there is no way of telling them apart.