Tip 1:

Water your grass early in the daytime (preferably before sunrise).  This helps minimize evaporation loss and limits the time your lawn is wet, thus reducing the potential for disease.

Tip 2:

Use slow-release fertilizers in order to extend the time frame for which your lawn and plants can absorb the extra nutrients that your fertilizer is providing. Most slow-release fertilizers have less of an environmental impact and are usually more cost effective than standard fertilizers.

Tip 3:

Applying approximately 4" of mulch to landscape beds, will both reduce weed growth in your plants beds and also help by retaining the moisture levels in your soil.