Most Helpful Guy
Bombard him anyway. Teach him the hard way to not be a shitty texter. :)
As awkward as it sounds, you might have to talk about things he really likes. Or of course, you could always do the above.. :/
It really isn't that easy to keep the conversation going, so good luck with your endeavor!
Most Helpful Girl
Text conversations are overrated. If he's a shitty texter then there's no reason to force it. Keep it in person or call him.