The seed variety is 50+ years old. So the specific variety (for example, the black beauty tomato) has been grown for at least 50 years (with new seeds of that variety being harvested, saved, and planted each year). Good question though -- I should edit that for clarity!
Did I understand you correctly - the actual SEEDS are 50+ years old? Are they kept in some specific conditions?
The seed variety is 50+ years old. So the specific variety (for example, the black beauty tomato) has been grown for at least 50 years (with new seeds of that variety being harvested, saved, and planted each year). Good question though -- I should edit that for clarity!