There are not any citrus that I know of that will remain at 3 ft or under. Even the "dwarf" varieties reach 6-8 ft.

What if you planted the tree in a container? "That would maintain the size of the tree". Maybe more of the Pro's will come forward?..I'm not one of them!. But you may consider it..Dale

That might be a god option if no one else has any ideas for a nice fruiting tree. It could grow higher than 3 feet high but I was guessing anything taller would get too wide to stay only 3 ft wide.

I have potted citrus on my patio and after a few years they do like to reach out, especially the Satsuma. Citrus don't really like being pruned, but if you opt for container trees you can stunt their growth somewhat by allowing them to get potbound. My potted Ponderosa Lemon tree is about 4 years old and has stayed small. It always has fruit on it.

There are lots of choices for your zone if you are also considering non-citrus. One of my favorites is Cherry of the Rio Grande, which takes pruning well and is lovely in appearance. Or "Condo" Mangos in containers, or apples on dwarfing rootstocks-those can be espaliered to be narrow and short.

You could grow Blueberries there, if you amended the soil to make it acidic. But most fruit trees besides citrus lose their leaves in the winter. Do you want bare sticks up against the house part of the year? I put up with the bareness, since the show they put on the rest of the year is so worth it!

COTRG stays glossy green all year.

Can you put gutters up to prevent rain runoff from damaging the plants?

Lisa

I would grow grapes on a wire trellis. I grow an acre of grapes, some table grapes but mostly wine grapes. My wife loves to make jelly out of wine varieties and passes them out to all her lady friends. Grapes are pretty much bug free, at least in Colorado - Millet

My two to three year old Thornless Mexican Lime, on Flying Dragon rootstock, planted in the ground, has remained at about 2 1/2 feet tall for nearly a year and a half. Maybe a growth spurt will come later, but from my experience so far, that scion/stock combination is my recommendation for a small area such as you describe. Some smaller varieties of mandarins on Flying Dragon are not supposed to exceed around four feet tall, but I haven't tried them.

How big a tree on flying dragon gets depends for a large part on how much you fertilize and how good the drainage. Poor drainage = small tree. Interestingly enough, last year my biggest trees for sale in 5 gallons were on flying dragon! Expect only about a 40% reduction is size for flying dragon and slower growth. Two of my trees on flying dragon only had one weak flush of growth this year and trees on trifoliate having 3-4 flushes so far.