Dianthus Capri 'Kocapri'
Words: Graham Rice
Fewer people grow perpetual and spray carnations at home, partly because the traditional way to grow them is in heated glasshouses, which are seldomly kept warm in the winter these days. This is a shame because it is also possible to grow them outside on the patio, and there are some gorgeous types which you’ll rarely find at the florist.
One carnation that stands out, and recently had its Award of Garden Merit confirmed, is spray carnation Dianthus Capri ‘Kocapri'. Each fully double flower measures 5cm (2in), and is a gentle, soft, pale-orange colour, which is just lovely; the flowers retain their colour whatever the season.
Capri is also unusually prolific. During the 2008-2010 Wisley trial, two patio containers with five plants in each produced 152 flowers in July and August alone. Under glass, with a winter minimum of 9oC (48F), Capri was also more productive than the others.
On the patio, Capri is at its best in high summer. Although the plants are floriferous, they become rather bare at the base so are best surrounded by containers of bushier plants. The pots can be left outside all winter if necessary, but it is crucial that drainage is good - they should be stood on pot feet to allow excess moisture to drain away. It’s also vital that plants be protected from too much snow or torrential rain. Moving them into a cold greenhouse or under an overhang should work well.
You can find out more about growing spray carnations in these trials reports:
Trial of Perpetual Flowering and Spray Carnations in Patio Containers 2008–2010 252kB pdf
Trial of Perpetual Flowering and Spray Carnations Under Glass 2008-2010 417kB pdf