An overgrown and/or dying lawn could give the impression that you're not around (or that you're just a seriously bad gardener). Depending on what your yard situation is, have your sitter mow, water or do whatever else needs to be done so that your property doesn't scream "vacant." Your oxygen-producing, environment-benefiting leafy beauties will thrive and you won't have to waste money, energy or resources on replacing them later, had they died due to neglect in your absence.