Many commonly found flowers are edible and the tastes vary widely from very mild flavours in flowers like violets, borage or mallow to peppery or fiery ones like nasturtiums, chives and wild garlic.
Always make absolutely certain you know what any flower is before eating anything.
I found a short article on delicious.magazine website about cooking with some easily identifiable edible flowers that you probably have around the house or garden anyway and that is a great place to start.
Here are just a few pictures of things you will recognise that you can eat.
Lavender
Dandelions
Honeysuckle
Oxeye and ‘normal’ daisies
Roses
Nasturtiums
Many flowers are lovely just as they are in salads, others make great cakes, syrups or jellies or can be used in pancakes, fritters or other savoury dishes.
If you like the idea of using flowers I really recommend Cooking with Flowers: Sweet and Savory Recipes with Rose Petals, Lilacs, Lavender, and Other Edible Flowers which contains a great mix of sweet and savoury recipes as well as excellent pictures and tips on growing, picking and storing your edible flowers. Click on the image below and it will take you to the book on Amazon – however, I quite understand many peoples have issues with Amazon and prefer to shop elsewhere. If so, have a look at Alibris UK
which is like Amazon but nicer and full of independent booksellers.