Can I dry the fruit out to make a plant?
Certified GKH Gardening Expert
Not really. The fastest way to make new blackberry bushes is by taking root cuttings. This should be done in January or February, when the plant is dormant. This article will help with that: https://www.gardeningknowhow.com/edible/fruits/blackberries/propagating-blackberries-cuttings.htm