Fruit straight off the vine is the best, whether you're picking crimson strawberries at a U-pick farm or growing bushels of blueberries in your own backyard. Nature's sweets is best consumed by the bucketful, and the getting is good for the short time they're in season.
Even the most ardent berry lover has a limit to how much they can consume, so if you see your new collection of berries becoming a little mushy and soggy, you need take quick action to avoid mold growth and avoid throwing away any delicious gems.
Although you may easily make a cobbler or berry jam with a lot of fresh blueberries, raspberries, blackberries, etc., freezing them is the best way to preserve them in bulk for months to come.
It's also a small gesture of goodwill for future generations. Nothing beats being able to take out bags of frozen fruit that still have all the juicy flavor and nutritious content when it's freezing outside and fresh berry season is long gone.
It's more simpler and easier to freeze fresh berries than many other home preservation techniques like canning and pickling, and it doesn't require any specialized equipment or expertise.
For a simple two-step preserving approach that will keep that awful mold at away, all you'll need is a little freezer area and freezer-safe containers, such as baggies or containers.