when do you fertilize your hay fields

I have both grass mix and straight Alfalfa fields, I fertilize after 1st cutting with 50-40-80 plus 5S and 10Br  on grass and  0-60-120 plus 5S and 10BR on the alfalfa. Then I give the Alfalfa the same again after 3rd or 4th. I think I need more N on the grass but if it turns dry after 1st cutting the N is leached out and never used. If I apply fertilizer before 1st cutting I could put on more N but that can cause the hay to be harder to dry down and gets coarse faster. Any suggestions I think I could go 80 to 100 units of N in the spring.I am going try applying before 1st cutting on the poorest yielding fields and may add some alfalfa or clover seed to the fertilizer. any suggestions thanks  

when do you fertilize your hay fields