I see that you are in Tucson (which helps because it is cooler there), but Jonathan requires 700-800 hours of chill (temps between 32-45). Unless you are in a really cold spot in Tucson, I can't imagine you having much luck with it. We get 250-400 chill hours here in Phoenix, but it depends on where you are in in the city.

The usual suspects around here (Anna, Dorsett Golden, Ein Shemer, Beverly Hills) do well here and you don't have to be that paranoid about heat. Fruit trees need a lot of sun.

I have Anna and Tropic Sweet (the latter out of Florida) that grow well, but they are low chill varieties . I've heard that Fuji may not be as low chill as people suspect. Pink Lady is a newer variety that looks interesting too.

Try this link.

http://www.davewilson.com/br40/br40_trees/br40Apples.html

Good luck.

In case anyone would like to know - my Jonathan Apple tree has 5 apples growing on it. There is no other apple tree for miles to provide cross-pollination. There were too few chilling hours to bother counting last winter. Yet, this little tree which I bought in a 5 gal. can in July of 2005 - has produced 5 apples. My plum tree, apricot tree, almond tree were suited for Arizona and the apple tree was not. The others all show heat stress but not so for the apple tree. It acts like a native. The almond tree, which is the same age as the apple tree, produced 2 nuts. Even my orange tree - which I bought in a 5 gal. pot in Oct of 2003 has not done as well as my Jonathan.

Yeah, I am interested to know. I enjoy comparing notes.

If I don't thin, I get about 70,000 tiny apples on my Anna and Tropic Sweet trees. With thinning, they get to good size and quality.

Let us know about the taste and quality of your Jonathan apples. Might graft a branch on one of my trees perhaps if you have good results from it.

When you go to that site I sent you, pick a low chill apple (or lower chill one) that has the same ripening season so blooms overlap for pollination).

Good luck.