Autumn is a good time to prepare your lawn for the year ahead, and the best time to tackle any long-term improvements. Tasks such as raking out lawn debris, eradicating moss, feeding, and aerating will improve the quality of your lawn greatly if carried out on a yearly basis.

Under some conditions, grass clippings and debris can form a thick "thatch" on the surface of your lawn. This affects growth of the grass and should be removed with a lawn rake. Raking also removes moss.

If grass growth is poor, aerate the lawn. You can do this by pushing the prongs of a fork about 15 cm (6 in) into the ground. Brush a soil improver into the holes made by the fork. Use sand or a mixture of fine soil and sand if the ground is poorly drained. Alternatively, use peat, a peat-substitute or very fine, well-rotted compost if the ground is sandy. Reseed as necessary; fall is an excellent time for reseeding.

If your lawn is in poor condition and needs reviving, apply an autumn lawn feed. It is essential that you use one formulated for autumn use, as spring and summer feeds will contain too much nitrogen. If the grass contains a lot of moss, apply a moss killer. Use one recommended for autumn use; the mixture known as lawn sand, sometimes used to kill moss, contains too much nitrogen.

You can (and should) tidy an uneven edge whenever it's necessary, but doing a full job of it in autumn will relieve the pressure at busier times of the year. Hold a half-moon edger against a board held in position with your feet.

"Why do leaves change color in the fall?"

If you've got a questioning child around, you may hear that often. But it's not really a child's question. Scientists have done much study on the question--and they still don't have all the answers. However, they do have most of them.

As most people know, the green in our plants is caused by chlorophyll, which plants use to make manufacture sugars for their food by photosynthesis. What most people don't know is that there are other pigments in many green leaves besides chlorophyll. These others are orange, yellow, and red (respectively).

During the growing season, new chlorophyll is constantly being produced as it breaks down--and the leaves stay green. When autumn comes around, the tree blocks off the connection between itself and the leaves, and chlorophyll production stops.

Once the chlorophyll breaks down, the other pigments have a chance to show their stuff. The orange and yellow pigments are produced (along with the green) all during growing season, but in the fall anthocyanins (the red) are manufactured from the sugars that are trapped in the leaf. And in plants where that happens, the others once again get masked, and you end up with reds and purples.

For the best red colors, it helps to have warm, sunny fall days and cool nights. You can find some trees where you'll see red on areas that get a lot of warm sun and yellow on areas that don't.

If you have a young child who is interested in the question, we found a nice kid's site (with little cartoons) that does a good job of explaining it (click here). If you're an adult who would like a far more scientific explanation, try this site.

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