Sadly these days, too many people only get their food from supermarkets, and are unfamiliar with local plant species. Some will pay upwards of £2 for a small punnet of blackberries, when almost limitless amounts can be obtained from local hedgerows.
Many hedgerow berries are edible or can be made into jams, jellies, wines or other preparations. An 'Autumn jelly' can be made with a mix of fruits (e.g. blackberries, crab apples, rose hips, rowanberries, haws and elderberries). Never use sloes as they will make any preparation very bitter. Elderberries have a low pectin content, and must be mixed with other fruit in order for a jelly to set. Rose-hips contain tiny irritant hairs and any preparation of these must be strained through a jelly bag. Fungi are best collected in the months of September and October after a period of wet weather. Some are highly poisonous, so only eat them if you're certain they're an edible species.
For the more adventurous, then making wines for the long winter nights is a very satisfying pastime. This is a guide to the common edible plants and what can be done with them. More to come as I find them!