When life gives you leaves, make leaf mold. When life gives you food scraps and ­garden clippings, make ­compost.

›› Margaret Hantiuk

Recently I attended an interesting course on soil science at our Compost Education Centre. I was reminded how important autumn is to gardening here in Victoria.

We have the opportunity to build up our garden soil with all the leaves from our trees and shrubs, to pile it up or use a chicken wire basket to make a wonderful soil enhancer: leaf mold. Try running your lawn mower over the leaves a couple of times first to break them down and speed up the decomposition. Left over the winter and added to the garden in the following season, leaf mulch not only adds nutrition, but also smothers weeds if applied as a deep layer of least 3 inches. In addition, it keeps the soil soft, moist, and cool around plants and provides a habitat for good worms and the microorganisms needed to help plant roots take up micronutrients. It improves soil structure as it breaks down. A layer of compost will do the same thing.

If you are food gardening, do not add pet feces or leaves from the public streets to your compost or leaf mold. As well, for the health of your plants, do not add diseased foliage (unless your compost is very active, heating up to the point of being too hot when putting your hand in)! The last precaution is to not put in weeds that are near the seeding stage or any part of invasive plants (morning glory, ivy, buttercup, and goutweed come to mind). Your compost should have an earthy smell when done, and not smell rank. Unfinished ­compost—as with wood chips, which are fine on paths, but not as a mulch around plant roots—actually robs the soil of ­nitrogen as it decomposes, instead of adding to it. Inoculate your compost with topsoil or finished compost from your garden.

Healthy soil consists of 45% minerals, 25% water, 25% air, and 5% organic ­matter. This means that your soil should not completely dry out—watering deeply and less frequently is best—and mulches really do make a difference.

Try to not stand in your beds, especially when the soil is wet, as in the spring. Build beds that are within an arm’s reach, with paths, stepping stones, or even boards arranged for you to stand on if you must go into a bed. Or, try raised beds.

As we learn more about soil, we realize that turning soil over inverts the natural soil profile. Try forking the soil, or hoe delicately (watch for roots, which spread out quite a ways around a plant). To make new beds, try sheet mulching with layers of newspapers and compost (weed first!). The fall is a great time to do this, and in spring it should be ready for planting. Mulching will soften and improve clay soils and add humus to sandy soils. You can have your soil tested at Integrity Sales on Keating Cross Road. They can then recommend any amendments that you may need beyond mulching. You can have your soil tested for heavy metals or contamination as well, if you are food gardening and have any concerns.

Lastly, remember that your soil is an ecosystem. Adding natural amendments allows the soil to improve and the ­microorganisms to flourish. Sea Soil may not be as good a product as Tuff Turf (a locally-made marine mulch), because Sea Soil may have marine material from fish farms. They use additives which you may not want in your soil to keep their fish stock free of disease. A free source of leaf mulch is available in the late fall from municipalities, but it is from the curbside leaf pick-up and so is probably not suitable for food gardening. Lastly, do not use peat moss, which is from endangered bio-systems (and it dries out too much in our summer droughts).

Enjoy your fall harvests and remember to put your garden to bed.