I went to plant a cherry tree in my front yard today and was surprised to learn that there is very little organic matter in the soil. There was about an inch of soil, followed by gravel. Eventually I'd like to get rid of the grass as I don't like the thought of watering it just to mow it. I'd like some advice about how I might go about improving the soil. I had thought about mulching with newspaper, followed by grass clippings or leaves, or maybe a layer of compost followed by green manure or cover crops. Thoughts? I have a carragana shrub that I could transplant into the yard, which would be helpful for building some organic matter. There's some saskatoonberries growing, and seem to be doing well. There's also a pincherry which is in bloom but has seen better days. The saskatoons will eventually take over that area, which is great. I'm hesistant to plant too many trees just to help improve the soil as it is a very small space. I think eventually I'd like to have a low maintenance yard (maybe a clover mix growing, or some low maintenance flowers....). Any thoughts on how I can get to that goal? Also, I live in northern Canada, close to Alaska, so that will affect the type of plants, cover crops, and trees/shrubs that I can plant. We are in an area that is classified as semi-desert, and therefore don't get alot of rain. The yard receives alot of sun as it is south facing. I'd like to work with the climate instead of against it, as my neighbours do with all of their fertilizing and watering of their lawns! Any help would be appreciated!
First thing I would do is to till in some biochar. That will help no matter what else you do and in what order. Figure 1 or 2 pounds per square foot to start with and maybe a similar application in another couple of years. Adding biochar first is the best thing you can do to give the soil bacteria and fungi a foothold and for everything else to get going. It may even help to perk up the pincherry.
Since the soil is so thin (probably scraped south by the last glacier to cover the area), you are going to have to figure out how to add sand, silt, and clay in addition to adding the organic amendments you mentioned. Have a source of used cat litter? That's valuable clay that you can be using to build soil. Any building sites around that have leftover sand from brick/block laying? Spread that out on the surface. Silt is a little more difficult to some across since it doesn't have much of a commercial market. If there are any stream banks around where you can dig a load of dirt, that would be beneficial.
I am sympathetic with your problem. I have a thin soil as well, anywhere from 2-10 inches, but it sits on clay that is several feet thick. While a little clay is nice, that much is kind of like gardening on top of a concrete slab. I have done all of the above: had tree trimming services dump their loads for me to spread, I search for places with leftover sand, and I'm continually having little bonfires to generate more biochar to till under. Well, not all, I don't have to do anything but dig down to find clay.
I've lived places with postage stamp yards before. One thing you could do is contour it some - like put a berm (hugelkulture/wood chips) along the front or add matter around the perimeter to make a "bowl"/pond in the center. Directing rainwater to keep in the yard for the rain you do get could be one goal. You could also put in some rain barrels under your eaves to collect water for watering later on, especially if you'd like to establish some food shrubs.
When we were setting up lots of aquariums they said to use the Wal-Mart clay kitty litter because they don't add any chemicals to it; a lot of brands these days add perfume, deodorizers, etc. Not sure what effect they'd have on lawns but we didn't want them in our fish tanks! The plants I put in grew very very well in the kitty litter, tho.
Clover makes a nice groundcover. You could also add in some naturalizing bulb flowers for a nice show in the early spring.
Cover cropping has some attractions. Roots would get down into the gravel subsoil. I'd aim to sow the crop so that whatever I grew had some size by the time the first frosts came along. Let whatever it is winter kill. Repeat the following year. I've done this using sorghum and various beans but didn't get the cover I was hoping for. Still, it wasn't bad and certainly was attractive in terms of the amount of effort I put in ... just buying and sowing the seeds. I'd mulch it afterwards with woodchip. I can source fairly cheap woodchip mulch from the town recycling centre. A lawn of woodchips is very easy to care for, and breaks down eventually into black, crumbly loveliness. Shrubs and small trees are happy being planted into the soil created by woodchips.
Good luck with it.
The system used by Back To Eden (see the online moie free) does a simple and easy way using a layer of composted manure and then a lyer of wood chips. This actually improves the soil - even the gravel.
As for the grass problem- check out http://NoMowGrass.com for a low maintenance lawn for you and your neighbors. There are other low maintenance lawn grasses on the market, but I highly suspect a couple of them are GMOs.