Place your vegetable scraps in your slow cooker.
Add enough water to your slow cooker so the vegetables are covered. Place the lid on your slow cooker.
Cook on low for 6-7 hours or on high for 1-2 hours.
Turn off your slow cooker. Strain your stock. You can compost or discard the solids.
Add stock to freezer-safe containers. Freeze or refrigerate. It will remain fresh in the fridge for about a week. It will keep in the freezer for around 6 months.