My garlic is about 50/50 brown/green, so today I decided that it's probably time to dig it up. I'm fairly new to gardening, and I'm learning things all the time. Today, I learned a little more about the amazing powers of chopped leaves.
Last Fall, I mulched my garlic with a 3 inch layer of chopped leaves held down by a thick layer of heavy, pressed straw (big pieces torn from the very large bales they use on big farms.) In late winter or very early Spring, I regularly checked under the straw chunks for garlic sprouts, and when I found them coming through the leaves, I removed the straw.
The chopped leaves really did a great job of blocking early Spring weeds, as I don't remember seeing any at all in my garlic bed. Some summertime weeds (kochia or "fireweed" and bindweed) did eventually develop a presence in my garden, but the soil was kept so amazingly soft by the layer of leaf litter that pulling them was much easier than "normal."
As I dug up my garlic, I realized that the leaves provided a number of amazing services. They blocked weeds. They also blocked intense sunlight from hitting bare soil and thus retained moisture and reduced the need for additional irrigation. The leaves fed the earthworms a buffet, thus attracting their valuable digging and aerating labor, and causing them to leave behind nutrients in the form of their worm castings or worm manure. The body slime the earthworms produce helps to maintain soil structure, too.
I had covered the entire bed with leaves, and I thought they were matted down and stuck down to the soil fairly well, but I was wrong. Early Spring storms in Kansas can bring winds of 60 miles per hour or more, and my leaves were blown off half the bed.
When I cultivated it, the half that was bare was gray, dry, hard, compacted, and weedy. The half that remained covered with leaves was black, moist, soft, loose, and almost weedless.
My new goal for the Autumn is to gather enough leaves to cover every square foot of my garden beds in 1-2 inches of chopped leaves. I have seen the light: chopped leaves are my new favorite mulch.
