Apple rootstocks for weak growers

[Hereford fruit grower]

I'd appreciate some advice on d'Arcy Spice which doesn't at the best of times make a large tree.

My existing apple trees are all on M9. This works very well except that on this soil (below) M9 is too vigorous for Crispin and not vigorous enough for Golden Russet.

d'Arcy Spice appears to need a more vigorous rootstock, like Golden Russet could have done with in 2013 if I'd known what a small tree it would make.

My soil is a well-drained but very moisture-retentive loam, pH 5.5-5.8, i.e. heavy and as far as I gather heavy soils are ideal for M9, hence my good experience with it. More vigorous stocks like M26, MM106 or ?M116 seem on reading various online documents to be more suited to lighter soils, which I don't have.

So is there any huge advantage in using a stock other than M9?

[ameno]

I can't vouch for comparative vigour, but all my apple trees are on M26 and they do well on my heavy soil (loamy clay).
I don't think it's that the more vigorous rootstocks prefer light soil at all. Rather, they can cope with it, whereas the more dwarfing ones can't, and outright need good soil.

[chrisdb]

Some apple rootstocks are less tolerant of very wet or waterlogged soils than others. Maybe that's what he means? See the discussion here for example:

https://www.growfruitandveg.co.uk/gr...oil_70008.html

My parents have a plot with heavy clay that is saturated for long periods during the winter, and they've lost a lot of the trees they planted on m26.

But since it sounds like that's not an issue, I'd think any apple rootstock should be fine. In fact, in fertile moist well drained soil, going for a very vigorous rootstock would probably be a mistake. M26 or mm106 are likely to be fine.

[Lardman]

How old is the tree ? From what I've read about DS it's very slow to get going (3-4 years) but picks up after but it's not one I grow personally. It's only available locally on MM106 which is a good indication that it need a bit more oomph than normal.

From what you've said previously about your trees I'd guess MM106 and M116 would give you something a bit bigger than you want have you had a look at PI 80 ?

FWIW my GR is on MM106 and is just about keeping pace with others on M26.