And is there any special fertilizer that you use? I have some second-year plants that are flowering now and would like to see them fruit this year.

Although I think that might be because I put out birdfood and because they seem to prefer eating the mulberries from the tree that's about a dozen feet away and will be fruiting the whole time my raspberries are fruiting.

I've never fertilized the raspberries, but it did take several years before my patch started fruiting. And many of the raspberry varietals are on a 2 year cycle. One year, they'll put up canes that spend much of the spring and summer growing straight up, with no fruit, and in the fall those canes will start falling off to the side, and they'll fruit at the beginning of summer the next year. On the two year varieties, after you harvest the fruit, you can simply cut the cane down a few inches above the soil, because it will never bear fruit again. You just want to be sure you don't cut down any cane that didn't have fruit that season, because they'll be the ones that fruit the next year. Not all varieties act that way though. I know some will actually bear fruit several times in the season, once early summer and then again later in the fall. Mine are all the two year types, though.