We had tried putting out thistle without success, until the Goldfinches finally discovered it in spring 2001. In spring 2002, we had two 6 port and one 2 port feeder up, often having to refill them daily! We went through several pounds of thistle until most of the Goldfinches finally moved on. The House Finches decided that they like thistle now, so we still occasionally refill the two port feeder, and will leave it up permanently. We will redeploy the 6 port feeders in the fall when the Goldfinches return (although we have seen a pair of Goldfinches as recently as May 10!).
If undisturbed, a Goldfinch will sit and eat for many minutes. Of course, that makes those waiting in the wings impatient, and altercations sometime develop!
In April we caught these goldfinches feeding on the ground... Jan remarked that they looked like a "herd of lemons". If you look closely you can see that there are a few females in the mix also.