Adding compost to your garden helps to hold moisture in the soil. Compost contributes to the soil's tilth, its texture, making the crumbly dark loamy stuff that helps plants to thrive. All true gardeners have at least one compost heap. A garden without compost is like hot apple pie without ice cream, or spaghetti with no gravy, or a truck with no engine, or a computer with no Internet. Well-composted soil will be a joy to plant.
Compost loosens up clay soil.
It helps sandy soil retain moisture and nutrients. It encourages worms to do their great work of aerating, churning, digesting, tunneling. It helps the gardener's back from going out. Meanwhile, make compost, make compost, make compost , make compost, make compost, make compost, make compost. Add compost to your soil, add compost to your soil, add compost to your soil, add compost to your soil, add compost to your soil.