The pucker is usually caused by a little too much water. It may also be wise to repot it into a larger pot, so watering is more consistant.

Thankyou so much ksrogers ! Ill back off on the watering a bit and see if that makes a difference...Ill look for a larger pot as well... :-)

Tomato leaves will do this same thing. When its overwatered many times, chlorosis will set in and the leaves start to turn yellow. Many people kill plants with kindness, thinking they need a lot of water. When I grow from seed, I usually only add water when leaves just start to show signs of drooping a little. Keeping herbs a little on the dry side usually helps them to produce more healthy foliage.

Some basils just have puckered leaves - at least some of the ones I've grown. Another reason might be aphids or other sap sucking pests.