Lots of wild and volunteer plants around this yard this year!
There is some purslane growing, which until recently I thought was a terrible weed - nonsense! - I'll likely use some in a salad tonight with some Lamb's Quarters (goosefoot, chenopodium). I also found a small cedar tree growing, and trees are useful for all sorts of things including sucking some of that CO2 back down into the soil. In our front yard, there are lots of sunflowers growing and milkweed. The sunflowers I imagine are volunteers from our neighbors, who plant their whole sidewalk area with sunflowers each year. I've been waiting for some to grow on our side! The milkweed popped up from plants last year, and we even saw some monarch caterpillars feasting on some earlier this summer.
Volunteer - Sunflowers, Milkweed
Wild - Purslane, Cedar tree, Lamb's Quarters
My 'technique' was just to let them grow, and clear a bit of space around them when they were small to ensure adequate sunlight.