Zinnias can take the heat.  Behind my house is a big old flower pot that used to be in the front yard. It fractured, maybe hit by a car, so I dragged it to the back yard as a soil bin, removing about half the soil for sundry potting projects over recent months. The remaining soil is all abloom with golden zinnias, not planted, but spontaneously reseeded from last year when the pot was out front. Because most garden zinnias are hybrids, the seeds from last year’s display give “surprises,” although pleasant surprises.

The volunteer zinnias do not care that I do not take care of them, nor that half the soil is gone, nor that there’s been no rain, nor that temperatures have soared into the 90s with blistering sun. They just want to be pretty.
Not so many bedding plants stand up to these conditions so enthusiastically, but Zinnias are largely Mexican originally, and thus adapted to solar abuse. They appreciate nice moist fertile garden conditions as long as there is full sun. They’re prone to powdery mildew, so sprinkled leaves are not optimal.

The core garden species is Zinnia violacea, and altogether there are 17 species and many hybrids and cultivars. They come in every bright floral color known, and may be big, little, double and puffy pompoms or sort of spare, all beautiful. A group I especially like looks like wildflowers, ‘Profusions’ are tough as nails…and bring on the heat. Most of the Profusion Series are yellow-orange, and others come in additional colors. Some zinnias are bred for mildew resistance, such as the Zahara Zinnias. Red-flowered Peruvian Zinnia has escaped cultivation a little bit in Florida.

Zinnias are fun to start from seed. They can sprout in just a couple days, but of course they come also growing in plastic trays. They grow and flower fast. Pinch the old blooms for renewed flowering. Not necessarily annuals biologically, they are for garden purposes annuals, some lasting several months.

The floral colors are so rich and vivid, they have historical uses as dyes for wool and leather, and as body paint.