I know everyone hates chickweed but I am going to be the devil’s advocate. I believe that mulch is useful even with our cold soil if we experiment different ways of using it.
I have plenty of chickweed and I have been using it to good advantage. I’ve always heard that any small piece of it will re-sprout and grow. I haven’t found this to be true when I use it right. I usually gather it when it is tall and before it seeds, without the roots, and take handfuls and twist it into short pieces and cover the dirt in all my pots one to two inches deep. This retains the moisture from sun and wind drying and the native earthworms love it. I add more whenever I weed. Chickweed has so much water that it rots very easily. I used grass clippings once from the local Post Office but I got a terrible dandelion problem and they don’t have the moisture to rot as well.
I also use chickweed to create planting soil. I cut it off just under the surface with a shovel or hoe, and then turn it upside down in a pile. Add a little extra dirt if necessary, which adds microbes to activate the compost quicker, and cover the top with a layer of dirt. If anything starts to grow, just add to the pile or cover with a little dirt. By next year at the same time it is almost all rotted. When I am potting anything I just add it to my dirt. Sometimes I create small piles wherever it is a problem and just leave them till I till next time. It makes excellent green manure quicker than anything else I have found. Humus is far more important than anything else I can do for my soil, and I am always needing it when I am potting. Whenever I repot with this I always get new growth quickly.
I like Typlar on the ground around my trees, and it definitely increases growth in young plants, but I also want to try using a mulch without this Typlar when my trees and bushes get a bit bigger. On my raspberries and currants every spring I lay down a good layer of year old manure/bedding which prevents weeds, retains the moisture and feeds the plants. I want to try doing this with my trees in late September / early October and then water very good. One of the best ways to warm the soil and retain moisture is to increase organic matter. The looser the soil the easier it is to warm. Wet clay is very cold. It may be necessary to cover with screen or hardware cloth if there is a vole problem because they love to live in big piles at least. Getting two cats has stopped my vole problem it appears. Voles were terrible before I got them in spring 2000. I don’t want to use any kind of poisons around the food we or our animals eat.
Small Farmers Journal reprinted articles from Britain in the 1940’s and 50’s that say that they used chickweed as an early pasture crop before planting other things. In the original plot I used to temporarily plant my trees, I planted oats and barley in an area to let our goats and sheep eat. When this and the chickweed got big and before the chickweed reseeded I tilled it in. I did this twice in one summer. It made very light soil. These reprints spoke of using mown clover and alfalfa, high nitrogen sources, as a mulch for the only fertilizer for fruit trees. Clover will convert inorganic minerals in the soil into an organic form also, which other plants can then use. Our old glacial subsoil is full of minerals. Sweet Clover and White Clover work excellently for this. I believe we can get all the minerals we need if we can get Sweet Clover to grow down into our subsoil. Alsike Clover grows excellently in roadside gravel so it is converting minerals there. What if we use it for mulch or compost it to add to our soil? We will get both nitrogen and minerals.
A very good set of books were written by Louis Bromfield. They have been reprinted. The two I can think of now were Malabar Farm and Pleasant Valley. He bought up several farms for a total of about 1000 acres in the 1940’s. These farms were in low production from to much chemical fertilizer and depleted humus. He rebuilt them into excellent production using green manure, animal manure, pasture and rotation farming. He even grew alfalfa when no one else in the area could because of the light soil he developed which prevented the frost from breaking off the tap roots. White, Red and Sweet clover were the important soil builders on his farm. This farm still exists today as an example.