They are called Chinese lanterns. You can see why from the shape of the flower. They are also known as winter cherry or bladder cherry. They are a member of the nightshade family like potatoes, peppers and tomatoes. The plant is used primarily for its decorative qualities. It dries well and makes a nice arrangement.
It has been around since the 16th century, primarily in Europe. The fruit has also been harvested, mostly in the past. It was valued for many years as being rich in Vitamin C. It is actually hidden inside the lantern-like flowers. Inside each one is the fruit which resembles a cherry tomato. Seeds are plentiful in the fruit and that is how you plant them.
Sow the seeds lightly in loose soil, pressing gently. Planting inside first is best then transplant in about 14 days. They will do well in sun or partial shade. The seeds scatter when left to themselves as soon as the sepals dry. This can be a problem with so many seeds. if you don’t want them to spread, pull off the flower before they re-seed.
This plant also has a problem with rhizomes so you might want to restrict its root growth by planting it in a pot.
The plant is very pretty, delicate and colorful, especially since it is vibrant at this time when so many other plants aren’t blooming anymore. It makes a nice centerpiece, dried, for your table too.