Some genetic dwarfs may have advantages over trees on highly dwarfing rootstocks, for specific applications. They are dwarf not because of weakness but because of short interstems - brachytic dwarfing. Examples include genetic dwarf peach, almond, blackberry, and tomato varieties and some annual farm crops. Since the dwarfing is brachytic, they may be growable on strong, stout rootstocks.
Im not up to debating why someone would want dwarf trees. Everyone has their own needs. In my case, I want fresh fruit, multiple varieties shapes flavors, that spread the harvest over a long season, in a small space, that I can prune, pollinate, thin, bag, spray, pick safely and in an accessible way for someone with physical disabilities. If someone wants large trees, massive crops, that’s great, go for it and be happy. Im happy with a few bowls of fruit per tree to eat fresh, can, bake and share and not so much waste. As for me, without accessible sized fruit trees, I might not be able to grow them. Some mini dwarfs do bear heavily and produce plenty of delicious fruit for the gardener.
What I wondered about was experience with these apples - do they taste good, are they disease magnets, do they fall over (like some on M27 or Bud-9), do they tend to overset and require >90% thinning (like brachytic peaches), do they runt out and die (like several I had on M27, including Honeycrisp and Karmijn), do they grow far bigger than advertised (like my Liberty and Jonagold eventually have on M27 even though graft union was a foot above soil line).
Looking at a New Zealand nursery web site, they claim that “Growing to just two metres tall with a mop head habit, this dwarf apple variety produces delicious full-sized crispy red fruit. Good natural disease resistance means little spraying is required, and little or no pruning is needed. Early ripening variety.” I don’t know if their variety is a rename or vice versa of the American variety.
The image of the genetic dwarf apple tree “Apple Babe” on the One Green World website:
It looks productive, plenty of apples, unclear how large the fruits are. Stout trunk, unlike what
I have on M27 or Bud9. Fruits appear well shaded by the plentiful leaves, typical for brachytic dwarf varieties (I had a lot of sun burned fruits in 2021).
On the other hand, there is $$$, nursery hype, and it would help to learn about real home garden experiences. If I buy one, I’ll be happy to report on it’s progress.
Thanks @mroot for your suggestion. It’s an interesting idea