Mulching is a lot of work and expensive if you have a large garden as I have. However, even if you can only do it every second or third year, it is truly beneficial.
There is a variety of types of organic mulch that can be used: leaves, pine needles, peat moss, straw, and shredded bark or hardwood. I like the look of a uniform color on all of the beds, as it unifies and smartens up the entire garden. I also prefer four to six inches or so when possible, so that it is thick enough to last and not wash away.
Mulch helps plants remain healthier and hardier by insulating and reducing weeds, and they seem to produce more flowers as a result, but that may be wishful thinking on my part.
In the winter, it reduces the effects of freezing and thawing, and it is a blanket, like the snow, protecting roots and preventing plants from heaving.
In the spring, mulch prevents mud splashing on the faces of our daffodils and keeps the soil cool for longer, thus preventing premature bloom during temperature fluctuations. It may also delay some plants from breaking dormancy too early during early warm periods.
During summer, mulch keeps soil temperatures more uniform, conserves moisture, and reduces the effects of drying winds and hot sun.
This year I'm going to try to be more sensible and buy more mulch and fewer plants!