I don’t know about the avocado, but I bet you could do a 2-3 ft raised bed that would give the fruit trees a great head start, but you will have to remember that they are raised beds and will need good watering.
Yay! My roses are in!
Some pics of what the roses may look like some day:
http://www.pbase.com/missy_gardenwhimsy/yves_piaget
http://davesgarden.com/pf/showimage/131352/
http://davesgarden.com/pf/showimage/112949/
http://davesgarden.com/pf/showimage/73731/
http://www.growquest.com/mini%20rose%20gourmet_popcorn.htm
I’ve also planted some other things with them. Soon as I pick up the mess and water it, I’ll take a pic.