Geneva 30 Rootstock

Great discussion elsewhere on interstems. I have apple trees aged one to six years that I grafted on Geneva 30 roots. I put support stakes on some but not others. Does anyone grow G30 without support? Has anyone had brittle graft union problems?

I have some leaners that I propped up but no brittle union issues.

I have three trees on G30. No support needed. In general I find anything bigger than the M9 type size is fine for me with no support. Also no problems with graft union breaks, but I have only three trees. I have had several G11 unions break even though G30 is supposed to be the bad one for that. Also Krymsk 1 for stone fruits has had unions break.


That’s good news Scott. Still wonder what they’d do in a hurricane. I still have visions of Isabel that roared through the shore.

I have Jonamac on G30.
Nice height for home growers and wide crotch angles promote early fruiting.
I still prefer G202. Similar size, no union issues and better resistance to soil pests.

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Yes what’s the deal with wooly aphid? Is it widespread? Wonder if we’ve got it here on the Maryland shore. G30 not resistant so I’m risking it.

A grower near me planted a few thousand trees on G30. She thought they would be freestanding but after 6 years, they have all started to fall over and they are installing a trellis system now.

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Thanks for this information. Something similar happened to my six year olds.

Just found this when I was looking over rootstock threads in general here. It made me think about the Methley (b/c need reliable self-fertile) I want to try: on Krymsk1 as a fan against a fence. Would the support from the planting stave off a graft union issue? If not I may have to rethink that spot.

Jim Cummins, godfather of the Geneva stocks, has told me that woolys shouldn’t be a problem in our region.

Thanks Matt, dodged a bullet on that one as I just blindly bought G30 due to blight resistance.

Update: G-30 looks like flash in the pan. Cummins Nursery put out their 2019 catalog today and as far as I can see it contains zero apple trees on Geneva 30. It appears they have phased out G 30 completely (edit: not true, see below, still selling it as rootstock). It may be many years before the verdict is in on Geneva rootstocks.

They aren’t phasing them out as far as selling rootstocks only. It is there only M7 sized rootstock.

You’re right, thanks for correcting. I wonder why they stopped grafting it themselves.

So far, I was satisfied with the 25 G-30 roots I got last spring. The only ones I lost were from over zealously rubbing sprouting buds on the rootstocks…(there sure were plenty of those) .where 2 or 3 grafts failed to take, and I killed the rootstock by leaving no bud to grow.

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This spring will be my 6th year with several G30’s. So far-so good. Seem to be self standing and all yielded in the 2-3 years. They grow well in deep, fertile soils and are productive. I’ve not lost any trees to breakage as I have from other rootstocks.

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I have G30 trees at a site very exposed to wind and with relatively poor drainage where M7 trees tend towards tilting and needing support but the G 30’s have performed fine for about 16 years, although I lost one tree that snapped at the graft union many years ago.

I think there may be a wide variability from site to site and region to region on how this rootstock works, but it isn’t a big deal to use a heavy piece of steel conduit at planting for insurance. I would recommend it over M7.

However, I generally use M111 because Adams CN doesn’t carry G30. 111 tends to anchor better for me than 7.