I tried growing purple mangosteen about 15-20 years ago but killed a few trees and after doing a lot of research, I realized that it would be nearly impossible to grow and fruit it in San Diego unless I had a greenhouse.
Anyways, I gave up on growing it and whenever anyone asks me about growing mangosteen in San Diego, I tell them not to bother because it’s a waste of time and money. I told this to my friend that lives just a mile or two from my house and when I visited him today, I was shocked to see that he ignored my warnings and proved me wrong. I told him last year that the plant won’t last one Winter unprotected outdoors and he planted it into the ground last year anyways and I was surprised to see the plant was still alive and even looked relatively healthy.
He’s had this plant for 6 years and had been keeping it under his patio and overhang of his roof for the last several years and also slowly adapting it to the full sun/cold.
Last year, around late Summer or fall, he planted it into the ground and here’s what it looks like today. I still don’t think it will survive very long outdoors unprotected but it’s at least survived one Winter outside. On a side note, last year, our Winter was very mild and I did not get frost for the first time in many years.
The community I live in is made up of houses packed tightly together with relatively small yards. I believe the large amount of fruit trees in his yard along with his Koi Pond is bringing up his humidity. He also waters his trees with pond water and perhaps the mangosteen enjoys that, I don’t know.
All I know is that my mangosteen didn’t seem to like temperatures below around 65F-55F. Mine died the firstWinter I put it out. Perhaps the close proximity of all the homes is holding in the heat from the surrounding area? I have no idea.
Simon