Blackberries are an amazing plant, perfect for the idiot gardener. If you start a patch it will be there forever, even if you mow over it. Case in point, I’m the idiot gardener and I have successfully started a 2nd patch behind my shed. Propagating works thusly, plant a plant and leave it alone; it’ll spread. Pruning helps but isn’t necessary and it works thusly: after you’ve picked all your berries, cut the spent canes off at the base. Cut the new canes back to 3 feet tall (roughly, mine are 4 feet because I completely SUCK at estimating lengths) so they’ll form lateral branches in the next season. Stake the canes and paws off until it’s time to pick.
Every night after dinner we all go outside as a family to pick our dessert and I save up the leftovers until I have 3 cups worth, then I make ice cream! You’ll need an ice cream maker for this.
Place 3 cups blackberries, 2 tbsp lemon juice and 1/4 cup sugar in food processor and puree the mess. Let it sit for 2 hours to macerate properly; 1 hour or none if you’re in a rush.
Pour mixture through a strainer because who wants to pick blackberry seeds out of their teeth while they’re trying to enjoy homemade ice cream?
Add 1/4 cup sugar, 1 tbsp vanilla, 3/4 cup milk, 1 and 1/2 cups cream (whatever milk fat content you want: 35%, 18%, 10% or whatever combo you like or happen to have on hand). Mix very well and pour into ice cream maker. Push button and voila!