So who said seedling trees are a waste of time? :) These gorgeous fruit are from self seeded trees in our garden that I left to grow, just in case. Yes, they took a few years to reach fruiting size, but they got there! The yellow plum is small and freestone (the fruit separates easily from the stone) so has proven to be very good for cutting in half for drying or other preserving methods. The red one is a proper blood plum with sweet deep red fruit, possibly grew from seeds from a supermarket plum. It's about half the size of the ones on the supermarket shelves but that's still big enough.
I've been using a damaged wheelbarrow covered in glass and a net curtain as a dehydrator. It's working very well.