Cannabis grafting

[zif]

I've been making a lot of 'new branch' grafts recently. I think they might take even more readily than the wedge graft, and are nice because of how many you can do in a small area in one shot.

Basically, you notch a stem where you'd like a new branch, cut a chisel shape onto the scion, and then tape it tightly into the notch (nothing fancy, I always use plain clear tape). On non-woody stems, they take really quickly.

Here's one about two weeks out, well established. It's the lower piece of tape.

I made the wedge graft above it at the same time, and it's just getting into gear. So that helped make 3 plants in one.

With 5 'new branch' grafts, and one wedge graft, I recently made 7 plants in one in a sitting. With the vigorous rootstock, it's looking like they won't skip a beat.

 

[GMT]

If you do another one, I'd really like to see the actual cuts you're making to achieve this. I've tried countless times and nothing has ever taken.

 

[zif]

If you do another one, I'd really like to see the actual cuts you're making to achieve this. I've tried countless times and nothing has ever taken.

Will do. I have a couple of plants I'll be culling shortly (thanks to successful capture as scions!), so I can take a few pics of this approach step-by-step. Should be this weekend.

 

[zif]

@GMT Here it is, step by step.

My experience is that grafting works best on actively growing plant parts. If you see sap on cutting, there's a good chance you can graft to/from that spot.

A good target for a new branch graft. The tape will fit!

Any stem thick enough to cut into without too much risk of accidentally cutting off entirely should work. That said, this is about as thin as I tend to use.

And I did almost top it! My general goal is to go about halfway into the stem, but this is by no means too far to work.

The scion can be any diameter, so long as it's smaller than the target stem. It's easiest to match roughly similar diameters, but this graft is very forgiving to differences.

Here's the scion, and the first leaf cuts I'll make to get it ready.

Overall, scions with petioles seem to succeed slightly more often than those without. So I make all of my leaf cuts on the leaflet end as shown. I'll also remove any growth, like the bottom right shoot, that might sap energy from the scion while it's getting established. Finally, if the top has leaves even this far along, they go as well. The main goal is to preserve moisture in the scion as it connects to the rootstock's 'plumbing' (xylem and phloem).

The last scion cut - the wedge.

You can see the meristem tissue that you're trying to match across the graft in that shot. Here, I've enhanced it on the left in a zoomed in version.

Any graft will work, if you can get enough contact between that tissue in the scion and the rootstock, for long enough, before the scion dies.

 

[zif]

Here's a side view of the cut.

I usually go for a slight asymmetry.

The blunter side will face away from the rootstock, the longer side towards the rootstock.

Then I wrap tape from one side to the other, so that it meets sticky side facing sticky side. This allows you to use it as a clamp, applying force to the graft by pressing the sticky sides together tightly.

It will also relax on its own as the joint expands. As long as you're not smashing the stem to smithereens, it's difficult to overdo the pressure in this step.

With this style of graft, your goal is to have good contact between meristem tissues in the dark green areas below. Good contact in the light green areas is a plus, but not critical.

It's also fine if the wedge doesn't perfectly fill the cut you've made in the rootstock, or, if the scion has a little bit of the cut area sticking out above the cut in the rootstock. This is horseshoes and hand grenades, not brain surgery.

Finished product.

Hope that helps!

 

[GMT]

Wow, hey thanks for that. Not how I was trying it at all. That's a great tutorial, some work has gone into that, so I do appreciate that level of response, above and beyond man.

 

[zif]

Wow, hey thanks for that. Not how I was trying it at all. That's a great tutorial, some work has gone into that, so I do appreciate that level of response, above and beyond man.

No problem. It's such a useful technique that I do my best to help everyone add it to their toolbox.

 

[zif]

A couple of follow up notes (ask questions if I've missed anything!):

• You'll know if you've gone seriously wrong within a day or two. The scion will wilt, then dry out. That's time to take it on the chin and try again.
• OTOH, if the scion has not wilted by day three, you're *probably* looking at a successful graft. Some might fail at that point, but it's rare.
• You can expect to see active growth in as little as just under a week, but sometimes it will take a lot longer. As long as the scion hasn't wilted, it will grow. If it's taking a very long time to grow, you can bend or top the branch above it to stimulate growth. You shouldn't need to, but sometimes it's nice to move things along.
• If you want to graft to the end of a branch, make the same kind of cut to the scion, but symmetrically. Then just cut off the end of the branch, cut a wedge right down the middle of the end (with a single slice - just as with the graft above), and jam the scion in. Tape it shut the same way, and you're off. With practice, that kind of graft will take at least 80% of the time. With practice *and* attention to detail you should be able to push that to 90+%.
• To graft smaller scions onto larger rootstocks, keep in mind the area of tissue that needs to overlap. You'll still target the same area, but only on one side of the scion and rootstock. Don't put the scion in the middle of the cut in the rootstock - line up one side as evenly as possible.

 

[zif]

A few pics of the wedge graft process. (Note, this was before I realized that keeping the petiole was a good move. It is a good example of how much growing tip to leave on the scion, though.)

And an example of that kind of graft working, 16 days later. (I swapped the tops betweens plants 1 and 2, so this is the sister plant I made at the same time. I just realized the scion showing the cut above was this one, #2. I know they both worked, though!)

 

[GMT]

That's kind of what I was trying and failing, only with flat ends don't laugh at me .

 

[zif]

That's kind of what I was trying and failing, only with flat ends don't laugh at me .

Oh - that’d be hard to get right (‘though I bet you could get one to work now and again).

I kept a spreadsheet through the first hundred or so grafts to try to iron out a good technique. Dropped bagging the scions or making fancy cuts on the rootstock, started keeping petioles, etc. while chasing higher success rates.

But, once you get the hang of it - it’s nuts how easy it is to whack together whatever plants you’d like!

 

[GMT]

Once you've made your Frankenstein plant, do you need to keep up-potting it /, trimming it's roots? Or will taking cuts from the branches be enough to keep it's demands in check?

 

[zif]

Once you've made your Frankenstein plant, do you need to keep up-potting it /, trimming it's roots? Or will taking cuts from the branches be enough to keep it's demands in check?

Maintenance is the same as for any mother. I keep mine small with pruning and a root trim/repot when they start showing they’re unhappy with the pot, but you can also up-pot to have very large mothers (with dozens and dozens of scions, if you like).

 

[zif]

The result of a good 'new-branch' graft. The left branch in the tape labeled '3' was dropped in that way.

 

[zif]

An 'approach' style graft, where two seedlings were wounded where there stems would touch, then taped tightly together. A week or so later, I was able to cut away the stem of one of them. I've tried this many times, but it's tough to get right.

 

[chilliwilli]

Will the different gravtings keep their flowertime or get they affected by the hormones of the stock?

F.e. if i craft a kush top on a haze stock will the kush top get ripe after 9 weeks and the rest of the plant is still in early flowerstage?

 

[zif]

Will the different gravtings keep their flowertime or get they affected by the hormones of the stock?

F.e. if i craft a kush top on a haze stock will the kush top get ripe after 9 weeks and the rest of the plant is still in early flowerstage?

Flowering time seems more or less totally unaffected. I grew a 123 day thunk on a 9 week rootstock plant. It kept going strong all that extra flowering time, and the rootstock harvest was normal. As were a few other faster scions on it, too.

Your kush on a haze example would be even better, b/c the longer plant as rootstock would generally make more sense.

 

[hanfiking]

lol this is literally what im doing now too, i have a dutch dragon as the base plant and i plan on adding 5 more, im opting for the wedge

 

[hanfiking]

Wow, hey thanks for that. Not how I was trying it at all. That's a great tutorial, some work has gone into that, so I do appreciate that level of response, above and beyond man.

good to see you here we had the same idea

 

[Spaventa]

A multi mother grafted together strikes me as a risky, eggs in one basket approach to keeping a collection. If that one plant gets sick and dies, you lose everything. I think sharing clones is the best way to preserve mothers you aren’t working with and have no immediate plans for. Just give 3 reliable growers the mother and any babies and don’t worry.