Weeds can be good. Chickweed is a very tasty addition to a salad. You can eat daisies too. Dandelions make excellent wine and don't make you pee the bed. The best wine I ever made was made from rosehips. You have to be very careful not to include any of those stiff little hairs in the finished product as they'll make you cough. Pansy and wallflower petals make a nice splash of colour on a green salad. Sorrel adds a lovely tang to a dressing but make sure it's the common sorrel, not sheep's sorrel which has a coarser flavour. Both young sorrel leaves and young nettle tops make lovely light spring soups. Ramsons leaves (wild garlic) are just as good as regular garlic. If you have spare gin you can make a superb liqueur from young beech leaves. Dahlia tubers are edible, as are fuchsia berries. Ivyleaved toadflax was once a popular salad ingredient, though I find it a bit too spicy. Scurvy grass will stop you getting scurvy but pick it at the seaside, not from motorway central reservations.