There are edible wild plants in your backyard that you can forage for and make a great salad from. No need to go to the farmers market, you've probably got edible greens in your yard you can eat. Identifying and harvesting edible plants is called foraging, but I call it free food in your yard.
Below are some photos for plant identification, but be sure you know what these plants are. These are fairly unique plants, but be sure, OK? And make sure the area you are foraging has not been sprayed with fertilizers, herbicides, etc. You don't want that stuff getting into your food. You can buy Leda's Foraging Book here.
Some Wild Edible Plants:
When harvesting dandelion, you can choose to leave the plant in the ground and growing if you want. Just harvest the outer leaves and the plant will continue to grow. The leaves get stronger tasting when the dandelion flowers, but I think you'll find the taste pleasing.
Plantain grows close to the ground usually. Once it sprouts its flower stem, you probably don't want to forage for it, as the older leaves are not as great to eat. They can be stringy.
Chickweed grows in nice big bunches, and if you cut off just the top 3-4" of the plant, it will keep growing. It self seeds if you let some of the plants flower and go to seed. Then you'll have more free food!
Garlic Mustard is a non-native invasive plant. I see it along roads a lot. Harvest it by pulling up the whole plant with the roots. This plant will crowd out native plants, and most states want to get rid of it. The leaves taste like mustard greens, though not as strong. It has some good vitamins, so eat up.
Violets grow like weeds. There are some cultivated varieties, but the ones in our yard are wild edible plants, and easy to identify. They are low growing and have white - purple flowers. Harvest the flower and stem for your salads. They look great on a dinner table.