“Grow more zinnias” is at the top of my garden to-do list this year, and who’d have thought? For years, once I’d outgrown my all-colour-all-the-time early gardening stage, I turned my nose up at annuals, especially zinnias, which I considered stiff and garish.
That changed a few seasons ago, after I received a sample packet of ‘Raggedy Anne’ zinnia seeds from Renee’s Garden in Felton, California. It wasn’t any ordinary seed packet, adorned as it was with a lovely watercolour of the contents– a zinnia with shaggy, quilled petals and nice paintbox colours.
The package was so pretty I planted the seeds.
And I was hooked.
I loved the flower style; I loved that they bloomed all summer and until frost once they got going in mid-July. I loved the non-stop perky bouquets they provided for the house, as no cost! I liked the bright colours; they made eye-catching pools of colour in my otherwise pastel scheme. I was impressed when a friend told me the late Christopher Lloyd planted clumps of zinnias at Great Dixter to plug gaps in his perennial plantings. “They allow you to splash around and show off a bit,” wrote Lloyd in a 2005 Guardian article I found. “Because they have not been dwarfened and compacted by breeders and have a freely branching habit, they retain dignity. [But] they grow large–a few big plants are so much more impressive than a lot of small ones.”
I expect there’s been a bit more zinnia breeding going on since Lloyd wrote that, but zinnias still haven’t lost their natural habits. Since my introduction to the tall ‘Raggedy Anne’ (Zinnia elegans), I’ve also grown ‘Hot Crayon Colors’ and ‘Cut and Come Again’ (Z. pumila), which truly lives up to its name, from Renee’s catalogue. (Vesey’s Canada also has a great selection of zinnia seeds.) While it’s an old favourite heirloom type, well branched (Lloyd would approve) and about a metre (3 to 4 ft.) tall, with big double flowers in a wide range of colours, the ‘Hot Crayon’ selection is from a newer series called Blue Point, or Benary’s Giant. They’re tall, dahlia-flowered beauties with better mildew resistance than older varieties, and the many types are packaged by seed suppliers in different colour schemes– for example, ‘Cool Crayon Colors’ in lavenders, rose, pink and white, and ‘Decor’, a combination of apricot and lime green blooms that I’m trying this year, along with the adorable orange ‘Little Lion’.
Not all zinnias are tall. My Uncle Ren favoured the 20 to 30 cm.(8 to 12-in.) tall Z. angustifolia, and Z. elegans Thumbelina, which made great edging plants in his garden. Last year I grew a spectacular foot-and-a-bit tall zinnia, ‘Orange’ from the Profusion series, a cross of Z. angustifolia and Z. elegans. It’s a charmer, hybridized by Sakata Ornamentals in several colours. The flowers covered three foot-tall plants, which mounded in a prominent place near the road in my front yard garden and caused many people to ask about them. “No, they can’t be zinnias,” they’d say. Profusion looked good all summer, didn’t get any awful fungus diseases and needed no deadheading–it’s ‘self-cleaning’, as they say. This year I’m growing ‘Cherry’.
Zinnias have been around for hundreds of years in the Western Hemisphere, and were grown in Mexican gardens before the country was called Mexico by Aztecs and Mayans. The double forms appeared in France in the mid-19th century and the first cactus and striped varieties were bred in the US after the flower became popular at the turn of the 20th century.
How to grow zinnias
They’re dead easy to grow from seed, so they’re good for a child’s garden. For earlier bloom, I start mine indoors in a seed-starting medium about a month before the last frost and grow them under lights. But they grow fast outdoors as long as you wait till the weather is hovering around 10 C. (50 F.) both day and night. They hate the cold and will refuse to germinate…new seedlings may wither and die. Space the seeds about 7cm. (three in.) apart and cover with roughly 1 cm (a half-inch) of soil and keep it moist.
Seed should germinate in five to 10 days. After they have a set or two of true leaves, thin them to about 30 cm. (12 in.) apart, farther for large varieties.
As with all annuals, frequent feeding with a balanced fertilizer helps keep the blooms coming, although I find zinnias pretty dependable in that department. The real secret is to keep cutting them to encourage more flowers. That should be easy! Cut the stems long and well back into the plant, which will help keep the plants bushy.
Ah yes, mildew
Powdery mildew can be a problem, especially in hot, humid climates like mine. It usually shows up late summer. Obviously good air circulation is important, so plants need room to spread their arms. Many of the new hybrids have been bred for mildew resistance, but try to place zinnias of all types where they’ll get lots of sun, which they love, and try not to water from overhead. If they become affected, spray the leaves and stems with a mixture one tablespoon of baking soda to a gallon of water. It’s an old remedy befitting an old-fashioned flower.