Consider the lowly lingonberry
Lingonberries are great edible ornamentals. You would want to plant them as a beautiful in all seasons evergreen groundcover even if they didn't produce lots of wonderful tasty red berries.
We offer many productive varieties. Our most popular is the Red Pearl. It is actually the least productive, but it still produces lots of great berries and its the most disease resistant and easiest to grow successfully.
It is also a good pollinizer for the very productive varieties we offer including Erntesagen, Koralle and Ida.
Plant them about one foot apart and they will spread via roots and fill in an area. They do need well drained soil and in our maritime climate they need full sun.
About Thanksgiving time, you can use the wonderful lingonberry rake we offer to pick a bunch of lingonberries. They make a delicious, brightly colored, rich sauce that tastes like cranberries but maybe better.