I'm planning to be out of the house for 5 days. I have onions that are pretty far along, peppers that just sprouted and some brassicas that have not come up yet. My plan is to turn off the fan and keep the heat pretty low in the house while l'm gone. Anything else I can do to help ensure their survival? I'm most concerned about the onions as they take water just about every day right now. I know there are self-watering trays, but they won't arrive in time. And no, I don't have a friend that could stop by to water. Thank you!