You can do short rows. They're not increases, but you only work part of the sts (where you want it bigger). You would knit, turn your work and work back across just those sts, turn again, work over the sts plus a couple more of them, turn and work on the WS. Keep doing this until you've added enough. To avoid holes you wrap a st at the end of each row where you turn, then when you knit all the sts again, you would pick up the wrap and knit it with the end stitch. Knitty
has a good article on short rows and wrapping a stitch.