I was thinking of planting fruit trees in them but I'm not sure if fruit trees can go in planters. Anybody have any idea? If I'm not mistaken there is such a thing as miniature fruit trees that might work? Or maybe you have some other suggestions as to what kind of yummy thing can be planted there?
Yes, certain varieties and certain types of fruit trees and fruit bushes can be grown in containers. The only kind I have personally grown is citrus. They have been easy to grow and have excellent flavor. I have them in large pots that we have to bring into the house every winter (northern climate). I have heard about fig trees being grown in containers, as well as blueberry bushes, and even grape vines. Most likely you can find types of apples and most other fruit that will grow in your climate, are specifically suited to container growing, and are tasty as well. Apples have been bred for various characteristics throughout most of human history; pears also. These trees can be grafted onto 'dwarfing' rootstock that keeps the tree small--this is simple old-fashioned horticulture, not GM (genetically-modified). I have an apple tree on 'semi-dwarf' rootstock growing in the ground and the fruit is excellent. A miniature tree of the same type whether planted in the ground or in a container should produce fruit just as tasty, depending on the nutrients it has available.
In your research, it seems to me you are looking for fruit trees that A) grow well in your climate, B) can grow successfully in planters and C) taste good. To find the best types of fruit and the best varieties for your climate, you might start with your county extension service. They usually have a website with information about what grows best in your specific climate. I would also not hesitate to call them with questions (your tax dollars at work!). Then I would look for good information about container growing--there's a highly recommended book called "Bountiful Container" that I have not yet read, but includes fruit growing info. Also I would spend time googling of course, try 'container growing fruit trees' as that seems to bring up a wealth of links. I would be certain to get good recommendations on the taste quality of the selections, since it's quite an investment of time, money and effort to grow these.
A fruit tree site that I am familiar with is Raintree Nursery in Washington State, http://www.raintreenursery.com/
. I didn't see specific info on container growing there but you could call and ask.
What a fun project! Good luck, and let us know what you find out!