Mandarin tree update

So my tough Texas satsuma mandarin tree (Citrus unshiu 'Miho') put on mandarins this year. It usually sets fruit every other year, but this time it rested for three. I don't know how it keeps going. My son gave it to me for Mother's Day back in 2004. Every winter, James (with a heavy sigh) moves it into the garage, then moves it back outside come spring. It's getting close to garage time again!