|‘The trick with indoor plants is to slow growth down so they need very little care while you’re away.’ Photograph: Getty Images/Dorling Kindersley|
If no one is around to water, or those around may be erratic (at best) at the job, then the only thing is to take matters into your own hands.
The trick with indoor plants is to slow growth down so they need very little care. Water all your houseplants well, then line the bath or sink with a thick wad of damp newspaper. Place your plants on this, so they remain damp and humid. Make sure they are away from direct light, and when you return your plants will have sat doing very little. You can leave them like this for a week. If you are going away for longer, put the plants on top of bricks and fill the bath to just above the top of the bricks. If the plants are in terracotta pots, capillary action will take care of watering for you.
You can make a smaller version of this with a washing-up bowl and a roasting tray (or something with similarly high sides). Turn the bowl upside down and lay over some capillary matting or an old towel. Drape one end of the towel in the water-filled tray. The plants will remain moist as long as the water lasts. This works just as well outside for young plug plants and seedlings.
For larger pots outdoors, you can either pray to the rain god or hedge your bets. If you can move all your pots to a shady corner, this will slow down respiration and thus growth. If you can’t do this, some makeshift shade netting, such as lace curtains, will work as well.
Make sure all your pots have saucers, so that if and when they are watered, at least the whole pot soaks up the excess. Also mulch the top of the pots with bark mulch or even just homemade compost to conserve moisture. You can make a temporary water feeder by recycling plastic water bottles (as large as you have). Fill the bottle with water and make a very small hole in the cap. Bury the bottle upside down in the pot and the water will slowly leak out, as long as the hole is tiny; too big and it will run through immediately.
If your pots are full of vegetables that don’t much like a week off watering, bribe your friends. Let them harvest whatever is available while you are away, or give them a cut of the future bounty. The more they pick things like runner beans and courgettes, the more there will be for you when you return.