The birds here aren't picky but, out of convenience, in March I picked up a bird seed from a "bird store." Unfortunately, within a few weeks, a bunch of seeds sprouted under the feeder and I thought that's the last time I'll use anything other than the cheap box store seed. But, out of curiosity, I thinned the "weeds" and let them grow to see what they might look like. Now I've got a nice cluster of sunflower stalks growing under my feeder. The squirrels took the tops of a few, but the heads have set on about 10-15 so it should be a good show in a month or so.