Dianthus needs to be added to the list of garden toughies that are water-wise, don’t mind neglect and outlast most other garden annuals.
Planted now, dianthus will flower through winter into spring and summer, and only by next autumn will plants be well and truly exhausted.
The secret of longevity is full sun and soil that drains well, which means they are good for coastal gardens. In gardens with heavy soil and a bit too much shade, dianthus can be grown as a long-lasting container plant in an area with lots of sun.
Like petunias, dianthus should not be overwatered as they rot when it is wet and hot. They perform best in cooler, drier weather.
Keeping plants neat is also easy. Wait until the flush is almost over and then cut plants back by half with garden shears. Plants shoot quickly after cutting and new flowers will appear within 3 – 4 weeks. Dianthus will flower repeatedly if cut back after flowering. Fertilise after cutting back.
Using dianthus in the garden
Pink, red and white are the shades most associated with dianthus, but there are as many variations as there are varieties: single or double blooms, picotee edges, frilled petals, bi-colour and tricolour flowers, dark eyes, fragrance and more.
- Very compact varieties are generally Dianthus chinensis. They have large single or double flowers and grow 20 – 25cm high and wide. They are best for edgings and borders.
- Taller Dianthus barbatus is a mid-border plant growing 45 – 60cm high. These are the traditional ‘pinks’ and they last well in the vase, having long, pickable stems. They are available with single and double blooms.
- Dianthus hybrids, usually a cross between D. chinensis and D. barbatus, have been bred for their profusion of flowers, even though the individual blooms are a little smaller. They have the boldest colours: shocking pink, neon purple and glowing crimson. They are also more heat tolerant.
Dianthus for containers
Many new pot dianthus varieties have been introduced, like ‘Pink Kisses’, which was used to support the breast cancer drive. These are compact, neat plants with single, often multi-coloured flowers. They can start off indoors and later be planted out in the garden or into a bigger patio container.
For fuller-looking containers double the number of plants. When it becomes crowded, pull out the extra plants and plant them in the garden. Water container plants more regularly and feed once a month with a liquid fertiliser.