What exactly do you mean by broadcast? Just throw it around?
I have used Super Bloom which is a mix in water type which lasts a long time since you only use about a tablespoon/gallon. I do it several times. I learned the hard way not to use bone meal since some loose dogs dug up several of my irises and displaced many markers.
I have also used Bulb and Bloom food that is 4-10-10 that I just scratch in around the rhizomes. I have also used worm castings but that is rather high in nitrogen to use in the rainy spring. I know two hybridizers who use the castings. I use it sparingly and mostly in the fall. I also use Super phosphate at planting time.
I am wondering if it is too early for fertilizer in KY. I hear borers hatch about the time the tulips bloom which may be early this year. So when the crocuses bloom, that I have heard is the time to put the Merit stuff out. But I am not an expert....
