If you are in soil and not using something like autopots, then there should be zero need. And should there be a need, filling up a bucket or watering can of water will put enough air into it as it is, you'll notice when you run a bath or the kitchen sink that there are many many air bubblues, large albeit, but enough, people actually do hydroponic grows using a "waterfall" as their means of adding the required oxygen to the water.
Don't fret about it, in soil the roots should not be saturated with water 24/7, as such at the time when they are not waterlogged the roots are getting air through the aeration of the soil.