Yes, Plants Eat Dirt!
A plant grown in naturally rich soil always does better: fewer diseases; larger leaves, flowers, fruit; more luster; better colors. It is time to experience it for yourself. Get your plants off the chemicals!
To prove it to yourself that plants eat dirt, try this (or remember it or imagine it): Sow a seed into a small pot of soil. Except for the seed, that pot contains 100% soil, maybe a cup of it. Watch the seed sprout and grow. Wait a few weeks or months (depending on how fast the plant grows). Remove the plant from the pot. How much soil is there, and how much root is there? Maybe there is 1/2 cup of soil left.
Put the plant back into the pot. Wait a year. Remove the plant again. There is quite possibly no soil left, except for a few traces of sand or perlite (or the other more durable components of soil). All of the edible portions have been eaten by the plant. For centuries, we have been growing crops (which are then eaten by livestock or by humans). How much soil have we made (with manure, dead leaves, compost, etc.) to replace the soil that we have consumed by eating (meat or vegetables, since it takes vegetables to raise livestock for meat)? I do not know how the "experts" arrive at their figures, but the estimates of how much soil we have lost and not replaced are astronomical.
Who Makes Soil?
Conscientious gardeners and farmers make soil. Composting, worm composting, manuring, and green manuring are all ways of making new soil to replace what has served us so nicely. When we "buy a load of topsoil", it is most likely simply moved from one place to another (usually it is moved from a farm with rich soil). Now, however, we can buy compost, and good compost is new soil that has been made. Not only is compost better than soil for your garden, it contributes to the replacing of depleted soil. By the way, the soil we inherited and exploited during the 20th Century was made by the planet, by Nature, by worms and micro-organisms. That took millions of years. When we have used it all, we can simply wait a few million years before we resume breathing and eating, or we can sit back blissfully thankful that we made enough soil (through composting) to replace what we borrowed.
What Can You Do about It?
To replace depleted soil, we need to get into the habit of making soil. Even if you live in a single room, you can make worm castings in a very small bin, and even if you have no plants to feed it to, you can donate it to a park or local bush. If you do not want to make compost or worm castings, at the very least buy worm castings and/or compost instead of buying soil for your gardens and houseplants. Buy a potting soil blend that is made with worm castings and/or compost. Doing this encourages more worm castings and compost to be made.
For more on this subject, see "Feeding" and "Fertilizers" on page 21 of Keeping Them Alive.
If it does not bother you to have no air to breathe and no food to eat, then you really do not need to do anything.
Raising worms (vermiculture) to make compost (vermicomposting) is an excellent idea. Earthworm of many varieties consume vegetable wastes and then excrete them as a nutrient-dense compost (worm castings is the popular term). In some commercial operations, worms are fed animal manure and then excrete a compost that is many times more concentrated than the animal manure, with far more nutrients that are immediately available to plants as fertilizer, and in far less time.
Earthworms just may save us from our own carelessness in terms of soil management. Because of the great need, and because of the amazing benefits to crops, massive commercial worm composting operations are now in operation. My worm composting bin is from Wood Worm Farms. Their bins are worm-friendly, easy to use, and sustainable. Wood Worm Farms want you to divert 60% of your home waste from landfill sites by vermicomposting.