I agree with HydeMarsh on the jap.millet it is a 60-70 days to mature millet as are browntop and prozo white. However pearl millet takes 90-100 days, and my past dealings with sunflowers, is if not planted by mid-May then they are not dry enough. Seeding rates...if you disk and broadcast 25 lbs.of millet per acre. Drill rate 10 - 15 lbs. per acre . All the millets will work on doves, what the dove have to do to get to the seed will have more to do with your attraction as what type millet. Doves are a WEAK leg bird that does not want to climb over a lot of clutter.(if your dove plot was pavement with millet seed and a pool of water to the side... Homerun ! ) Keep your ground as clean as you can. If you have a drill, maybe tape off every other drop to give you 14 inch rows instead of 7 in. Making hay is always good, shakes the seed out and picks up the stems. Try leaving small strips of millet standing...dove like getting in the shade, and with wide rows should have bare ground to pick seed off of. A soil test will tell you how and what fert. to use but, at least 150 lbs. at planting and another 50-100 lbs high N fert. at 8-10 inch tall with a rain event coming. Good Luck !