Colourful zinnia an autumn delight
Want colour in the garden? Try zinnias. These splashy annuals are perfect for the autumn garden. They are known as short-day plants, meaning the shorter days trigger flowering. While they do still produce flowers in summer, zinnias bloom more rapidly and frequently during autumn.
Zinnias are among the brightest and most varied annuals, coming in almost every colour, even two colours (bicoloured) or with speckles. They are cheerful contenders for the picking garden, flowering relentlessly over a long season and lasting 5-7 days in a vase. You may even get them to last a little longer if you give them a floral preservative. A warm, acidic solution improves hydration and thus vase life.
Pick zinnias when they are (just) fully open. Cut flower growers will pick them just before pollen is visible or as pollen begins to form. Add a floral preservative to your vase, or make your own. To a vase of lukewarm water, add 1 teaspoon sugar, 1 teaspoon household bleach and 2 teaspoons lemon or lime juice.
Zinnias are easy to grow from seed, but at this time of year it might be better to buy seedlings from your garden centre. When planting, choose a sunny spot in free-draining soil. If you have heavy clay soil, plant in raised beds. A little bit of wind can actually be beneficial, as zinnias are prone to powdery mildew. The wind will increase the air circulation, and thus reduce the humidity around your plants.
Water consistently, but don’t overdo it. A saturated soil may result in root rot. I feed my plants fortnightly because I grow them for picking; if growing for displaying in the garden, once a month should be adequate.
Earwigs can be a problem on zinnias, although in my garden they much prefer my dahlias. The annoying critters can eat holes in buds and petals. They hide out in moist spots during the day, so if you think you have earwigs, roll up some damp newspaper and leave it lying beside your plants. Check during the day to see if they have taken up residence. If so, dump the newspaper in a bucket of soapy water.
Which varieties to grow? There are many to choose from – it really depends on the colours or forms you like. But usually the zinnias you find at garden centres are not named. You will find
A crop of zinnias in the garden guarantees more autumn colour than just the changing leaves.
them in the seedling or potted-colour section, and you can simply choose them for their colour.
If you want to be more specific in your choices, growing by seed is the best way to go.
Online nurseries have a good selection. You might try sowing some now (zinnias flower up to the first frosts) or sow them in spring.
The ‘Benary’s Giants’ series is one of the top choices among cut flower growers, with dahlia-like flower heads up to 15cm wide and stems 90-120cm tall. They have an excellent vase life and are recommended by the Association of Specialty Cut Flower Growers. Seeds are available online at Niche Seeds. The Dahlia Flowered Gold Medal Mix from Kings Seeds is similar, with stems reaching around 1m high.
Zinnia ‘Envy’ is subtly elegant with its pale green flower heads. It looks superb mixed with white flowers, both in the garden and the vase, with each flower measuring 7.5-10cm across.
‘Envy’ grows up to 60cm high, but if you want a taller version, try ‘Giant Lime’. It has 10-13cm fully double flowers and grows up to 1m high. Both are superb cut flowers and available from Kings Seeds. Zinnia ‘Zinderella Lilac’ is extremely unusual with its scabiosa-like flowers in bright lilac tones with a dark eye. Stems reach 75cm high, making it ideal for cutting. It’s a new edition to Egmont Seeds’ catalogue, available online.
Whatever your choice, zinnias are certainly a cheerful edition to the garden. Mass-planted they can turn a drab patch into a vibrantly fab one.