photo: Centaurea cyanus Black Magic
2007-03-24. Bachelor Button/Cornflower. Austin, TX

March 29th, 2011
Centaurea cyanus ‘Black Magic’

This post was published originally on 2007-03-24 and updated with data for 2008 and 2011.
The seed packet from Botanical Interests gives the common name for Centaurea cyanus as bachelor button. For us southerners, bachelor buttons are Gomphrena globosa. Julie at the Human Flower Project recognized it immediately as a cornflower, even though it was not the blue once so commonly identifiable that it is found in a box of Crayola crayons. I was going to go into a rant wondering whether children today connected their crayon colors with real flowers. The truth is, I’ve never seen a living cornflower before I grew this one. And then I chose a selection which is not cornflower blue.

Why don’t I like more cheerful flowers? This cornflower is a deep, plummy purple, a funereal maroon that, in flower marketing, is referred to as black. Morticia Addams would like it–she wouldn’t even have to snip off the flower before creating her bouquet. The plant itself is about two feet high with silvery gray foliage. From a distance, the dark flowers look like furry black caterpillars attacking the plant.

The seed packet said that cornflowers were drought tolerant. However, I’m not sure that translates into heat-tolerant. As soon as the mercury touched 80 today, they drooped. Instructions say to plant them in early spring before the last frost…unless you live in the south, of course! We’re suppose to plant them in late summer or early fall.

I planted these on September 11, 2006 and they just bloomed this week (late March 2007), more than six months later. They sprouted quickly and I transplanted them into the meadow close to the yellow irises thinking that the purple and yellow would make a nice combination. The irises aren’t blooming yet. None of Austin’s mild winter freezes bothered them, not even the ice storm or the night we got down to 25 degrees. They sent up flower spikes about the same time the cilantro did but took a long time to form buds and even a longer time for the buds to open. Every day I looked, expecting to see them open, and every day the flowers remained a tight closed ball. Then I went to New York and when I came back they were blooming. Maybe a watched cornflower never opens.

Dateline: 2007-2008

Discovered some seeds left over from last year and planted them in the west border where I’m clearing out the bearded irises that rotted in this summer’s rains.

The cornflowers (I still want to call them bachelor buttons) are about three inches tall and have two sets of true leaves. They are being smothered by competing baby blue eyes, so I dig up the whole bed and replant only the bachelor buttons spacing them about 5 inches apart.

In the mid-70s today and tomorrow. Transplant more bachelor button seedlings. From one group by the agave, three groups: 10 in place, 10 by butterfly bush, and 8 behind maiden grass.

First flower. Even though I planted the bachelor buttons two months later than last year it seemed to make no difference. They bloomed in exactly the same week. I prefer to plant them later if I can because then I don’t have to water as much and besides, I’m always running behind.

I think I will always grow bachelor buttons now because they are so easy and economical, although they did not self-sow. Two years of flowers from a $1.79 packet of seeds is satisfying. The effect is less somber than last year mostly because I have allowed the cilantro to overrun the meadow like a wave of white foam.

Dateline: 2010-2011

Sow half a packet of new seeds. Botanical Interests. 1 gram @ $1.79. Unseasonably warm ahead of a predicted hard freeze. Today’s high: 82°F; low, 70°F.

First flower. I never managed to thin these bachelor buttons so the plants are crowded and short. This dry spring has encouraged an abundance of pink evening primroses behind them. This is one of those unplanned combinations that bring delight.

photo: Centaurea cyanus Black Magic
2011-03-29. Bachelor Button/Cornflower. Austin, TX