What are some maintenance tips on hanging plants for kitchen garden?

For me, I make sure they are hanging by some good natural sunlight (ie window) and take them down to the sink occasionally to make sure they're getting enough water.

You can put a diaper in the bottom - it will help the plants stay moist for a longer time. Also, get a watering can with along spout to reach all the areas of the pot.

It's easy to keep watering in one area of a pot.

Take them down to water, especially if they have drain holes. That way you can see you are watering the whole pot and not just one area and also you can let it drain in sink instead of dripping on your counter or window sill. See if you can find one of those wands you can use to check to see the moisture level in the soil. It makes it easy to check the hanging pots especially if you are height challenged like me and need to have stools to get anything from the top shelves of cupboards.