I use bulb fertilizer. The same stuff I use on my Narcissus. I put some down when I saw new growth this winter, again a month or two later when I saw buds, and I will do some more maybe in late summer/fall. Mine are very healthy looking and really blooming well. I water them regularly (1-2 times a week) in summer when it's hot and dry, and I water them in winter/spring when they are growing. We've been very dry and had little winter/spring rains.

They do not require much in the way of fertilization. And they are not all that picky about soil pH. I do not fertilize much of anything in my garden and never have - there is just no need - but I do mulch consistently with compost.

Like gg, I've never fed anything outside the vegetable garden. Just add compost whenever there's a batch ready.