I just did a quick search to find this:
http://www.gardenseeker.com/pruning/pruning_buddleja_buddleia.htm

which seems to indicate that earlier is better and March should do fine. I'd do it now because you're a zone warmer than me and I've already got willow budding up here.

I didn't search for the fertilizer for you. :p I just wanted to warn you against fertilizing too early! you don't want to send it into a growth spurt when it should still lay dormant in this colder (freeze-prone) weather.

Yes do it now, I always cut mine back in Feb..and I wouldnt fertilize now either. Good Luck

I wait till I see leaf sprouts at the base of the bush and/or along the stems, and then cut back to that. A late heavy frost can cause die-back if I prune too early. It may also depend on what type of buddleia you have. Some are hardier than others. Mine does better when I wait.

Like susan, I always wait until I see new leaves coming out and I prune it right down to the new growth at the base. It is nearly the middle of April and mine haven't been pruned yet. I am just now starting to see new growth on mine this year. We are also going to have another short lived cool snap and rain over the week end so I am thinking that I may be able to cut them back the first part of next week
Penny

I didn't cut mine back , it was green so I left it.... and it is leafed out to the top. Not sure which kind it is but it was a 6 inch stick last year , got it for 6 dollars and now it's taller than me. Couldn't believe how it grew so quickly.