"Question Everything"

[NE PA QDM]

To paraphrase Einstein.

Short story: I grafted EARLY this year (zone 6, mid March) and my grafts DID NOT DIE.
Long story: read below

This is somewhat of a philosophical post (feel free to stop reading if I offend your sensibilities).

Conventional wisdom is that you can't graft in the field until the threat of freezing is past. This year I decided that I don't like conventional wisdom; I decided to "question" it.
My educational background is in biology with just a tiny amount of botany. I didn't understand WHY it wouldn't work to whip and tongue or cleft graft in March. Some of the explanation (I hope maya et all will provide further opinions) is that the scions or graft unions will freeze. But the scions/branches on the trees in the orchards don't freeze, so I thought this to be an insufficient explanation. A frozen graft Union seems harmful, but a frozen bud on the end of the scion is indeed consistent with naturally occurring conditions.
So, on 3/13/16 I started cleft grafting to "top-work" my existing trees. On 3/20 and 3/21 it was 20 degrees. The 10-day forecast looked warm-ish. On 3/23 I finished grafting (mostly cleft, some w/t) on last years failed grafts. Last year was my first year grafting, so there were plenty of failures around to try on!!!

By 4/15, we had several nights with low temps of 20 plus 20mph winds.
In spite of this, of the approximately 50 grafts I tried this year, more than 95% are already leafed out and it looks like the few holdouts might leaf out as well. Most of these grafts have between 6-12" of new green primary growth above the graft Union so I'm quite optimistic.

All are on either mm111, Emla 106 or m7. Many different early and late season Varieties were grafted. I will post a list below.

So, perhaps we should question the advice to wait until April or May to top-work. Maybe I'm
Missing some hugely important data point, but given my near 100% success rate (and my novice grafting status with about 60% success last year) I think this deserves further consideration.

Partly I tried it because my scions were starting to have mold problems in spite of bleach use, and partly I did it to see if I could.

So far, I'm happy I tried

 

[NE PA QDM]

 

[NE PA QDM]

All graft unions were generously covered with parafilm to insulate the graft Union and almost all scions were completely dipped several times in wax to somewhat insulate the buds. Maybe this helped?
This one of the only pics I took, Whitney crab, you can see the graft Union and new growth above it

 

[NE PA QDM]

This years' grafts were of the following varieties: Grimes golden, Whitney crab, honey crisp, smokehouse, Uralian butter, empire, sweet bough, ashmeads kernel, zestar, Spartan, redfield, golden sweet, prairie spy, ramsdell sweet, jonagold, northern spy, jonagold, Roxbury russet, Yates, yarlington mill, porters perfection, and a few others I can't recall off the top of my head
My goal is to have fruit dropping from June through November; Arkansas black gold rush and a few other late droppers were grafted in the last 3 years.

 

[NE PA QDM]

 

[Turkey Creek]

Interesting trial you did. I am pretty sure you wont offend anyone. As I have stated a number of the times in the past grafting techniques and success is highly influenced by local growing conditions. I know of others who have had grafts subjected to below freezing temps with seemingly no ill affects as well. I have a degree in Biology as well so I am always experimenting a bit, so with that being said your data will have more substance when you have repeated the same process over a few different years with varying weather conditions.

The reason that top working is typically done later in the spring is that you speed up the time that it takes the scion to callus to the under stock, as the under stock is actively growing. It would appear that your scions were sealed well enough that they did not dry out prior to the callus forming.

Keep us informed, always interested in what works for others.