How to keep plants alive?

I am going on a long vacation soon, and I have a variety of plants such as cactus, violets, marigolds, etc. The problem is, how do I keep them from drying out? Should I leave them outside? Is there a way to keep plants alive such as putting a bag on it?





-Thanks

How to keep plants alive?
Marigolds are outside plants,just ask a neighbor to water for you.The cactus should be fine,just soak them in a large bowl of water over nite.The violets just fill their reservoir before leaving.Ask for help if you can.
Reply:water crystals that hold water during dry spells. bags would be a bad idea..