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Bachelors buttons aka cornflowers (Centaurea cyanus)
This common, well-loved, old-fashioned flower is an annual that’s so easy to grow and comes in a nice, hard-to-find blue. It almost grows like a weed, reseeding each year. But it’s early and gives a refreshing start to the cut flower season. The flowers are edible and support beneficial insects.
Flowers are 1 ½ in. wide. The species is “Cornflower Blue” the color named after the flower, but there are several varieties now that offer more colors; (almost) black, plum, pinks, soft purples, and white.
They bloom in early summer and last up to two weeks in the vase.
Plants get to2-3 ft. tall and 2 ft. wide. The foliage has a light silvery surface and the stems have wing-like structures along them.
It comes from Europe where it has declined in numbers but ironically, its use in gardens has enabled it to naturalize in North America and Australia.
Growing the plants
The seeds are cute little things with a tuft of hairs at one end, looking like a floating sea creature. In my area, in Zone 9 they can be direct sown in the fall or in the late winter to early spring. If your area is colder, you may be able to do the same, or you may need to start them in cells or flats and plant out in spring.
Full sun and fairly good garden soil. Once established they can withstand some drought.
Beware of bachelor buttons reseeding and establishing itself as a weed in wild spots. To help prevent weediness, harvest the flowers often enough to prevent them from developing seeds. For this reason you may not want to get over enthusiastic about them, just plant a few.
You can cut them back by midsummer for more flowers in the late summer into fall. (But…there are sooo many other much more fun flowers to grow!)
Harvest long stems with several flowers and buds on them. With the wing-like structure on the stem it opens too many cells to strip the stem, so I just leave them on. If water gets murky, change it often.
I have grown the straight blue species and the mix with pinks, white, and blue. My preference is for the beautiful blue. But there are very nice plum colored ones available: Black Button—all dark plum, and Classic Magic—a mix of dark plum and pale, plum and white flowers. I may need to try some this year.
How many plants
I recommend not overdoing these if you’re short on space. But if you aren’t, they are pretty.
A fun thing about cornflowers is that they’re edible. Take the petals off the flower and use fresh to top salads, to dress up cakes, or use as a garnish for anything.
Or you can dry and store them in a jar to use to add color to tea blends and seasoning mixes made with herbs from your garden, or on salads, cakes, and garnish just like the fresh ones.