The previous owner had an unknown dwarf citrus that died but the root-stock lived. It's probably at least 20 years old, but it's been very neglected. I've been kinda ignoring it, and the darn thing is still growing despite only watering it once last year. It gave us a few huge seedy fruit that had a nice lemon flavor. I think Cuban Shaddock is also sometimes called Yuma pondarosa.

Anyway, we have a lot of yard space so I decided to just grow it anyway. I fed it this spring and pruned out all the deadwood and it's responding nicely. My other dwarf lemons are very young so I won't get much fruit for a while, so in the meantime I'll use the shaddock as a lemon juice source.