Take a freegan approach to your landscaping project. Instead of racing to the nearest home improvement store or nursery and purchasing every supply, think about free resources at your disposal. Have a friend with a green thumb? Ask for clippings of your favorite plants from his or her garden that will grow well in your yard. Know someone who works at a nursery? Find out if you can inspect the plants the nursery throws away for any salvageable ones.
Some city governments will give away mulch or wood chips as well. If you start a compost bin early enough, you can convert your trash scraps into an enriching additive for your soil. Also, evaluate which trees or plants in your yard could stay put instead of totally clearing your yard.
However, stay away from becoming a green-thumbed Robin Hood. Stealing clippings from public places such as parks or botanical gardens often carries significant fines if caught. Plant thieves at parks in Bridgeport, Conn., for instance, must cough up $50 in fines [source: City of Bridgeport]. Also, digging up native plants in wooded areas and replanting them in your yard harms the biodiversity of the area.