Plant buckwheat as winter mulch.
Surprisingly, buckwheat is not wheat, or even grass.
Its arrow shaped leaves show it is closely related to rhubarb. Frost kills it. If our winter is frost-free, you could expect pretty white flowers in spring, appealing to bees. Seeds are similar to sunflower seeds. In April, treat it as green manure. Dig it into the soil to add nitrogen.
Just scatter buckwheat seeds around your garden, vegetable and also flower bed. Let nature do the rest. West Coast Seeds has it in bulk packages.
In theory buckwheat dies when frosty, and rots quickly.
In South Delta, buckwheat doesn't get the ' frost ' message. Plants mature into lovely white flowers the next summer. Bees love them. Because they grow tall and airy, buckwheat can be left to grow with your summer veggies. They will self-seed for fall plants. Or collect the seeds to grind for your home-grown pancakes!