Those of us that grew up in the '60s and '70s remember the flutey goodness of Jethro Tull that blared from our AM radios. So when I found a quirky little Coreopsis in my garden center a few years ago, I had to smile and of course, had to buy it. No, I didn't buy it for its name (although I sort of liked that, too), but for its hollow petals.
I grew 'Zamfir' before that, and while it's similar - one of 'Jethro Tull's parents and enough alike that I could be happy with either one - it didn't grow well for me, and eventually died. 'Jethro Tull' has done much better and looks like it's having a stellar year for me in 2010.
Petals that look like this are called 'quilled.' Quill pens, used in centuries past, are made from bird feathers and are hollow, which is how quilled petals got their name. Several flowers have these characteristic petals, including Cosmos 'Seashells', several Dahlias, Echinacea, Chrysanthemums, and Osteospermum. Mums and Osteos take it a step further with some having spoons on the end of their quills.
Jethro Tull (1674-1741). He was an agriculturist and inventor of several products that changed the way growers did things. He improved the seed drill and invented the horse-drawn hoe. He modified the plow, and his changes can still be seen in the plows used today.
A cursory search for confirmation that the Coreopsis was named for farmer Jethro and not rock band Jethro, turned up nothing. So I decided to get on the phone and call Itsaul Plants, LLC, the hybridizer that introduced it. 'Jethro Tull' gets its name from the former - the farmer.
And now you know.
Photo of Jethro Tull band from Wikimedia Commons.