Post-Grafting & Pre-Planting

I'm having difficulty finding info on what to do with rootstocks immediately after grafting. Only thing I found was Cummins Nursery says to put them in a plastic bag for a few weeks and keep them cool using the refrigerator if necessary. Completely seal the bag? Is this for water retention? I've also seen someone whip and tongue onto a planted rootstock in a greenhouse. How much does any of this matter?

Thanks
Mason

Hi Mason,

We graft around one thousand apple trees each year for winter bare root sales (in Australia). Post bench grafting we put the trees straight into a big tub of water (with compost tea added), no more than 24 hours later we move them into moist sawdust inside old apple bins, they sit outside in the shade and will be transplanted into the nursery prior to dormancy ending (which for us is before October).

I wouldn't bother with plastic bags and refrigeration, simply keep the roots moist in sand, sawdust or whatever and transplant into the nursery or their final location prior to dormancy ending and you'll be fine. Apple trees are pretty tough old things when it comes to grafting.

No real reason to worry...
For my part, when I order rootstock they come in a box, packed in a plastic bag filled with some wet material.
Once I am finished grafting, I simply put them back in the same package (and spray a bit of water to make sure the roots stay wet), and leave the box in the cidery (where the temperature is pretty stable around 8 degrees C).
I never had any problem.

Jolicoeur Orchard
Zone 4 in Quebec
Author, The New Cider Maker's Handbook

So the reason for waiting to plant after grafting would be that it's too cold outside? And we graft early so the wound will callus while it's still dormant? But if it's warm enough to plant immediately after grafting that's OK but may be too late for successful grafting?

I'm in 4b, 5a & 5b.

I appreciate the responses.

-Mason

No reason to wait (in my climate anyway which is equivalent of zone 8), you can plant immediately after grafting. I only wait because I'm grafting so many plants it takes me weeks to do them all then I plant all in one go. Maybe if you're still getting really hard freezes in your colder climates I'd wait before planting.

The wound won't callus whilst dormant, the plant needs to be growing for the graft to callus over.

This University of Kentucky paper says to store rootstocks at 55-60°F for 2 weeks after grafting for callusing then to drop the temperature down to 45°F or lower for storage until planting. That's the first mention of doing this that I've come by. Any thoughts on this vs. storing them at ~ 45° post grafting?

[simpson.ca.uky.edu] › r...PDF
Reproducing Fruit Trees by Graftage: Budding and Grafting

We'll that's interesting, our grafted apples will typically sit heeled in outdoors, in the shade for about two weeks (some longer some shorter) post grafting in approx that temp range but still freezing most nights before we plant them out.

I think you can follow those suggestions if you really want and you have the ability to store at those specific temps but I'd not worry too much, we've found grafted apples trees to be pretty foolproof as long as you keep them cool and moist in-between grafting and planting.

The problem with setting out your rootstocks too early is that the scions can dry out before they establish a support relationship with the host rootstock, especially if your nursery is in a sunny spot, (not preferable.) While I see that others here with more experience than I are having luck otherwise, (I have a couple hundred successful grafts under my belt, and still have problems getting it right with some species,) I have the best luck with moistened sawdust on the north side of my garage for the first week or two, (watch out for extreme temperature drops, new grafts may not have what it takes to protect them from unexpected Arctic blasts,) until I see the buds on the scion begin to push open. Then I plant them in the nursery, (if you don’t have a shady location for this, you can create a shade structure with a sheet and fence posts-just be careful it doesn’t fall on any fresh shoots.) Regular watering with a light mister or watering can until they have a couple inches of growth helps as well. As Claude says, apples are quite forgiving. Children, dogs, and my own clumsiness have lost me more apple grafts than any other fault in their care.
Good Luck