How to get the best results
1 Sow seeds only when the ground has warmed up and frosts are firmly in the past. Colder, more northerly parts of the country might not be suitable for zinnias, as they like plenty of sun and warmth, a legacy of their South American origins. Sow two or three seeds 5cm (2in) apart, at 30cm (12in)
spacing and around ½cm (¼in) deep. It’s best not to sow zinnias in seed trays as they don’t like root disturbance, so don’t always respond well to being pricked out.
2 It’s best to sow them directly into finely raked soil in the spot where they’re to flower as they don’t like to be moved. Add compost to speed their growth, and the seeds will germinate rapidly, in as little as three days. When they germinate, thin the seeds out, so you end up with one plant every 30cm (12in).
3 Try growing zinnias in containers for moveable splashes of colour. Choose shorter varieties, such as ‘Zahara’, as these will do better in pots than the taller ones. The potting soil should be kept continually moist and when you water, make sure that it doesn’t touch the foliage. Fertilise with a water-soluble plant fertiliser once a month.
4 Keep them well watered. They like warm, moist soil and full sun, though they’re prone to damping off and botrytis if conditions get too cool and wet, and can develop mould which rots into the heart of the plant. Many seeds are sold with a coating of fungicide to avoid this problem.
5 Zinnias have thick stems, but to guard against flopping when you plant the taller varieties, support each plant with an individual stake. Opt for a decorative one in rusty iron, for example, to turn a functional item into an attractive feature. Deadhead the flowers regularly and you should get a flowering period of around 10 weeks. You can dry the flowers, too, making an attractive indoor display during the colder months.
6 The flowers are best known for creating a riot of primary colours, but there are some stunning pale varieties to choose from. ‘Benary’s Giant White’ has multiple rows of creamy petals, while ‘Isabellina’ is pompom shaped. The pale G A P ones look particularly effective when grown with a limegreen variety called ‘Envy.’
7 Butterflies love zinnias, which makes them an ideal addition
to a wildlife garden.