So you're going away on vacation? Your plants are not, and there's no reason for them to suffer in your absence. With a little planning, they can thrive even as you stroll the streets of some exotic city or canoe pristine waters. Unless your vacation is slated to go on for weeks and weeks, your main concern for your plants should be water. Two hot, sunny, summer days without water won't faze a tomato plant out in the garden but could kill a pot of marigolds. Your first job, then, is to identify which plants have similar thirsts.
With the exception of succulents, including cactii, which store water, the thirstiest plants will be those that are lush and growing in pots. The pots that dry out fastest are those that are porous, such as unglazed terra cotta, and those most bathed in air, such as hanging baskets and window boxes.
Other plants for which watering is most critical are any that you planted in the ground only within the last couple of weeks.
Other plants in vegetable and flower beds, as well as established plants and even trees and shrubs you planted in spring, should be able to sit out your vacation happily enough without supplemental water.
Even potted plants can survive a short vacation if moved to a shady spot shielded from wind, and perhaps stood in saucers with a bit a water in them. Not too long, though.
You can water from afar
So how can you get water to those plants that really need it?
A reliable friend already familiar with your plants is best. To ease your plant sitter's chores, group potted plants with similar watering needs and have hose and watering cans standing ready and nearby.
Another option is to rig up something that waters plants. One way is to group potted plants together and lay in each pot a small, commercially available drip tube which feeds off a half-inch plastic pipe that is connected to your spigot through an inexpensive water timer. The Oasis Self-Watering System has its own reservoir and tubes leading to plants.
You also can keep plants watered with devices that wick water to dry soil. Aqua-Stake is a hollow, ceramic spike topped with a water reservoir; press the spike into the soil and water oozes out. Water siphons are similar, except the ceramic spike connects to a water reservoir via a tube. A length of thick polyester rope pushed through the drainage hole of a flowerpot, with the rope's end splayed out into the potting soil when the plant is potted up, could act similarly with its other end in a water reservoir.
(Drip tubes and ceramic waterers are available through such suppliers as www.charleysgreenhouse.com, www.dripworksusa.com and www.urbanfarmerstore.com.)
The wicking concept has expanded into self-watering pots (www.gardeners.com). Such pots have a reservoir, either underneath or built into the sides, from which water bleeds as needed into the potting soil.
Test any automated watering system for a few weeks before you leave for vacation. Set up correctly, these systems do such a good job that you may decide to let them care for your plants all summer, whether or not you are away.