How can I grown my hair longer without the ends splitting?

I’ve had hair down past my waist for several years; over that time, I haven’t had it trimmed very often, with the consequence that it got a lot of split ends. Today, I broke down and whacked about 5 inches off, which took care of most of those (and I’m hunting down the survivors with a pair of scissors). However, all this was with the long-term goal of getting it long again—with luck, even longer than before, but not so ragged. How can I do this without the ends splitting? My hair doesn’t grow that quickly; I’m afraid that getting it trimmed frequently enough will undo any growth. Thoughts?