For filling in those large areas, try horseradish, or Jerusalem artichoke with its showy yellow flowers.
Shade tolerant veggies include beets, brussel sprouts, cabbage, garlic, leaf lettuce, spinach, turnips and radishes. Once you taste the flavor in your homegrown delicacies, you'll be increasing your crop every year.
Edible flowers are both decorative and tasty when added to salads and soups. Some of my favorites include:
Nasturtiums - Adds a peppery flavor to salsa and gazpacho.
Anise Hyssop - Sweet anise or black licorice flavor.
Basil - Flowers have a similar, milder taste than the leaves.
Bee Balm - Use leaves and flowers to make tea with an Earl Grey flavor.
Borage - Large shrub with purple star-shaped flowers that taste like cucumber are wonderful in soups and salads.
Calendula - The bright orange flowers taste similar to saffron with a peppery taste that adds a golden color to foods.
Carnation - Has a peppery, spicy flavor.
Chamomile - Tastes similar to apple and makes a relaxing tea that's easy on the stomach.
Chicory - The beautiful bright blue flowers tolerate the worst of growing conditions. The roots can be used to make a coffee substitute, the buds can be pickled similar to a caper, and the young leaves make a nice addition to a salad.
Chives - Flowers have a mild onion flavor and the chopped stems are a nice addition to soups, salads or just about any recipe you would add onions.