It was a bumpy ride for the zinnia. Like dahlias and red pokers, the flower’s popularity has grown and declined since its peak in the mid-20th century. But browse any nursery catalog and you will see that we are entering an upward phase.
There are brilliant images of zinnias in Day-Glo colors and with acid-lime streaks. There are massive double pom poms, shaggy “cactus” tips, and simple tall singles. Ruffles, feathers, and layers abound.
But where this heat-loving, attention-grabbing annual once was most associated with flat, tough bedding, bloom now taps into our desire to be unruly and wild. Zinnias can mix it with sculptural dahlias and cannas and with puffy cosmos and dill. They can hold out in the vegetable patch.
In fact, their role as a companion plant is part of their current appeal, attracting butterflies, bees and other beneficial insects. They’re also perfectly aligned with the growing popularity of seed saving, being best grown from seed rather than seedlings as they hate root disturbance.
They are also not resistant to frost or humidity, but are otherwise very accommodating, so much so that they have even managed to get into the space. About five years ago, zinnias became the first flower seeds successfully sown by NASA astronauts aboard the International Space Station – albeit with the help of fans to reduce humidity and lights. LED playing the role of the sun.
Back on earth, David Glenn, owner of the Lambley Nursery in Ascot near Ballarat, says he only sows zinnia seeds directly in the garden when the weather warms up in November and December. He says he finds that zinnias were bred earlier, but shelters in pots are more likely to eradicate diseases that cause young seedlings to collapse and die.
Others, however, get good success – and a head start – by sowing them early in seed culture mix pods and coating them with vermiculite to help protect against fungal infections. But they should be kept in a warm, sunny place at 20 ° to 22 ° C, and the seedlings then hardened and transplanted before the roots exceeded their space.
Whatever happens, don’t be tempted – even with all the extra time and the impatience of containment – to put them in the ground too soon. They will not survive. Zinnias, native to the Americas, especially Mexico, love warm soils and lots of sun. Under the right conditions, they will sprout in just over a week and, with minimal comfort, develop into exuberant flowers in two to three months. But good drainage is crucial.