When you start a new perennial border, spread non-woven polypropylene black landscape fabric over the soil. The fabric keeps weeds under control, holds heat in cool spring weather (giving your plants a faster start), and lets water soak through to the roots. At a local garden center, buy a nonbiodegradable fabric that weighs about 3.4 ozs. per square yard (about $10 for a 3 x 25-ft. piece). Use U-shaped metal stakes ($2 for a pack of 10) to hold down the fabric.
If you're building a fence, a retaining wall or a planter, set a course of protruding stones in the soil beneath it. That way, your mower can cut all the grass—no trimming by hand needed. The stones should protrude about 4 in. from the wall and stand at least an inch above the soil so grass doesn't creep over them. You will still have to pull out grass from between the stones occasionally.
A sprinkler isn't always the most efficient way to water your plants, especially if you live in a hot, dry climate. Soaker hoses ensure that the plants get most of the water, and you don't need to spend $25 at a garden center to get one. Give your worn-out hoses a second career by converting them. Just plug the end of the hose with a round stick and perforate the hose with a sharp nail. You'll get a free soaker hose and conserve water at the same time.