The perennial dilemma of amateur gardeners the world over: To water or not to water? You probably already know that some houseplants, like succulents, thrive in arid conditions, others need watering every other day. Keeping track of the thirst of each of your plants, however, takes a vigilant eye. Take some of the guesswork out of watering by employing a moisture sensor meter. The convenient little device tracks the conditions of the plants' soil, giving you a hint as to when to water and when to skip the liquid. Available on Amazon; $7.99.