The ones that produce the large seeds are Sunzilla (hybrid), Russian Mammoth, California Greystripe, and Mammoth. Birds are fond of the Black Oil variety. If you buy these multi-pound bags of them to feed to the birds, put 10 or 20 on a damp paper towel in a plastic bag and set it in a warm place to see if they will sprout. They probably will unless the seed has been heat-treated to prevent it. If you find some packaged or bulk human-edible large varieties that you like in the grocery section, get the 'raw, unsalted' type and test them, too. There are many seeds and grains that you can buy for human consumption that will grow, either for edible sprouts or growing in the garden, far cheaper than buying named varieties. Of course, if you want a named variety, you'll have to pay $3-4 for 20 seeds (or so), but the birds don't care. Sue

I wasn't aware of this. People grow sunflowers in their community vegetable gardens in my town every year. I found one study that showed damage to a typical weed plant grown in a hydroponic solution that contained crushed sunflower petals. You could probably compost the seed hulls without harm, but I'd probably just throw them out.

Very nice! It's hard to imagine eating sunflower seeds without fingers but he does it so well. I'd never noticed the shape of the cardinal's bill where the upper and lower meet. it's not just a flat surface like a hammer and anvil, it's zigzagged which must be more efficient. The tongue must be very active too. Interesting! Claire

I'm sorry Eric. I had thought that you had grown the sunflowers in an old birdbath. So you had transplanted the seedlings to a garden bed? I have grown some of the smaller Sunflowers (colourful Italian hybrids) in the past because they tend to give many more blooms than the larger types and are better for use as cut flowrers. The plants still usually reach about three feet tall with flowers from 4"-6" across. I wonder if the root system was damaged after transplanting and it just took a while for the plant to establish again. I have always found that Sunflowers are very hard to transplant. Mike