(ARA) - As the air turns cooler and the days grow shorter, our backyard gardens surrender their last fruits and vegetables of the year, and the last leaves fall from the trees. When we pull out the yellowing vines from the garden and bag leaves from the yard, we're a little saddened that we must wait until spring to see new growth again.

Autumn, however, is the perfect time to begin a project that will ensure a bountiful garden next year: a compost pile. Harvest time is a great opportunity to start a compost pile because decaying vines, vegetables, leaves and grass clippings contain excellent nutrients that break down over time to recharge soil with nitrogen for spring planting.

Building a compost pile is simple with these easy tips from the lawn experts at John Deere. First, find a place for your compost. Drive four 5-foot wood or metal stakes one foot into the ground. Fence in three sides with chicken wire, leaving one side open for easy access. If you like the idea of a compost pile but don't have time to build one, purchase a prefabricated compost unit.

Next, collect chopped tree leaves, grass clippings, and all the vines and fading plants from your vegetable garden and build a pile that's at least three feet in diameter and three feet high.

This will build a hot internal temperature that gets nutrients "cooking."

Flowers also contain many nutrients that are great for composting. If your annuals have gotten "leggy," pull them up and toss them in the compost pile and till the bed. Leave the fall perennials while the leaves are green, and then mow them down once they turn brown and compost the leaves.

Add the material in five- to six-inch layers and sprinkle a 10-10-10 fertilizer -- ten parts each nitrogen, phosphorus and potassium -- on top of each layer, and add a dusting of lime to prevent odor. Cover each layer with soil.

Shape the pile like a volcano and make an indentation on top to catch rain. Water the pile occasionally to keep it moist and turn it once in a while to move drier outside material into the middle where it can break down into lush humus.

To avoid odor and bothersome animals, never deposit meat or bone into the pile. As a safety precaution, avoid adding diseased plants or lawn clippings that have recently been treated with herbicides or weed killers.

John Deere also suggests waiting at least four mowings after the lawn's been treated before composting grass clippings.

Instead of having the autumn blues, turn your attention to a fun and easy project that will ensure a healthy garden next year. Compost now and in the spring, your garden will get a shot of nutrients that have been cooking all winter long.