I store my photos in Flickr. A few years ago, someone contacted me about purchasing (for real money!) a couple of garden shots. Recently, I was contacted by a nursery in France regarding my 'Limelight' hydrangea photos. No remuneration for the latter, but they did credit the pix. View them here.
Most nurseries use profession photographers to produce impossibly beautiful images for their catalogs. But doesn't it make more sense to show the plants as successfully grown by the average gardener?