If you only have a few pots or small trays you can put a piece of polythene in your kitchen sink, place several sheets of newspaper on top, soak with care, place your pots on top and water well. If you have too many for the sink, use your bath. You will need more light in the bathroom so put in a light on a timer. To have an irrigation system indoors is a costly exercise as you are only going away for a week.

You can buy capillary matting. Basically you put one end of the mat in water and stand your plants on the rest of the mat.As the plants suck up water from the mat the mat sucks up water from the water supply which could just be a bowl of water in your sink or bath.

I think Doctor Bob's advice above is using the paper as a capillary mat.

I have also used an old tea towel into the sink onto the draining board. It acts like a wick and draws water up. Newspapeer as Drbob suggests would do just as well.