By going columnar you limit you choices when a dwarfing rootstock, like EMLA 9, would allow you to choose any kind of apple you want and would work just as well within that space if you staked it. The columnar apples I've tasted aren't that good.

If you chose to grow peach, the columnar idea might be good. I've no experience with columnar peaches, however, as they are quite new.

I have North Pole. It's about 9 years old. Even columnar trees need pruning. I cut back the stubby branches to keep them under a foot long. Otherwise the tree loses its columnar shape. I also cut the top off at about 8 or 9 feet so I don't need a ladder. It is much more productive than my minidwarf trees. The apples are pretty good, mild flavored. Link is a photo of the tree in bloom last year - not the greatest photo but the best I have.

Here is a link that might be useful:

Columnar trees are not more productive than trees grown on root stocks of similar vigor to my knowledge. Sounds like yours has the vigor of about M26 which is a very productive semi-dwarf.

Harvestman -- when you suggest a dwarf rootstock like EMLA 9, how do I go about looking for trees like that that are commercially available? (I assuming you weren't suggest I do the grafting myself -- that's beyond my garden talents or interests!)

Are there trees you suggest to go with the rootstock that would be productive and health in such aa setting?

And (oh, if it were only true!) is there some place I can order that kind of mix-and-match tree? ("I'd like root stock X from column a, and fruiting top Y from column b....")

Appreciate the advice!

You can also check the availability at other nurseries like Adams County. Sometimes the larger commercial suppliers have larger trees than cummins.

I would question how fruit trees would do, growing over a cement slab. It the slab has some drain holes, one would probably have to treat the area above it like one would when growing items in pots. Dwarf trees or small fruits might grow there with careful attention, but I doubt a large tree could survive over concrete. Northwoodswis4

I have Scarlet Sentinel and must have the ideal climate for it, as they're really good; sweet, juicy, aromatic. It did well in a pot a few years, and must have had soil temps around 120 as the black pot got stinking hot in the sun. I can't complain about it's productivity either, as it is always loaded and gives two crops per year; we're just finishing up the winter crop now, which on the bare tree looks like Christmas ornaments. It would do OK over concrete, as heat doesn't bother it a bit. We let ours branch out as it wants but it is still stubby, not much over 3' wide.

Applenut

I've found that Arkansas Black (spur type) grows in a very compact columnar form on M7. I purchased 40 of them almost 10 years ago and they all grew in half the space of any other M7 trees. They're a very hardy tree and the fruit stores forever, improving in flavor over time. We have a waiting list for Ark Black and open the orchard just for those on the list at the end of Oct or the first weekend in Nov. I would stake the trees for the first 3 years.

Same can be said for Goldrush as what Kapple says about Arkblack.