I'd noticed this trait in some tomatillo varieties (like what I think was "Gigante Verde" from my local grocey store), while others ("Purple de Milpa"?) spoil in days.
I've been working to breed a variety with the long-storage trait, deep purple/black fruit, and decent fruit size. The longest I've had a fruit last at room temperature was 1.5 years, from harvest to planting in the 2nd year. I expect it would have lasted longer, but I wanted the seeds for planting.
The long-storage trait appears to be dominant, making it tricky to filter out the poor storage version of the gene.
They outcross so strongly and I have limited room, so I had to grow out different seed populations in different years. As a result, it has taken me several years to get to this year where all of my plants seem to have the long-storage trait, with some having the purple color I want.
