I've now officially become one of those gardeners who has specific dates for routine seasonal activities.
I realized last night that when the tree frogs begin to chirp at night—an event that usually begins around the first of August—is the time when instinct tells me to spread the previous year's compost over the flower beds.
August is a very dry, hot time in the upper midwest, and mulching the beds with compost now will help keep the soil cool and moist into the autumn. The plant material added to the compost heaps last fall have now broken down fully, and emptying the heaps now also creates space for the shredded leaves and other plant materials that will become available as I begin to take care of fall cleanup beginning in a few weeks.
In addition to the compost itself, I'll also start adding the grass clippings to the garden, over the layer compost. Up to now, those grass clippings have gone into the compost bins themselves. Some gardeners believe that raw grass clippings are a problem if they are used to mulch beds directly before they have been allowed to break down, but I've never found this to be a problem, largely because I d0 feed the gardens anyway, and the breakdown of green grass clippings never causes the nitrogen deficiency that is sometimes bemoaned. As the grass clippings turn to the color of straw, the visual effect is pleasing, as well, looking like a lighter shade of shredded bark.
If you mulch with grass clippings, though, you should do so only if you are not treating the lawn with herbicides. Adding chemical-laden grass clippings to flower beds may have bad effects on your flowers.
I"m not one of those gardeners who insists that all plants must be surrounded by clean, pristine soil. In the routine, day to day acts of deadheading old flowers and removing stalks, I snip up these bits and spread them over the garden as I go, so that the beds themselves do their own composting all summer long. Small twigs picked up from the lawn also get broken up and spread between the plants, so my gardens tend to resemble a forest floor in many ways. This isn't at all evident from a distance, though, so my gardens look quite manicured from a casual distance.
Next spring, the gardens will have quite a bit of organic debris that has wintered over the top of the soil, and rather than raking all this off, as some compulsive gardeners do, I will simply dig this material into the soil before planting time. The overall benefit of this approach is that it reduces the amount of fertilizing you need to do, as well as keeping the soil friable and easy to work with.