Some pictures - age 7-13 days...

Believe it or not, 500 grafts is not going to take you very much time to make once you get going. It only seems like a lot right now as your just getting into the swing of it.

With that being said, welcome to the wonderful world of grafting. I think many of your grafts are doing better than mine!

These look good, but maybe you saw my post about those that stopped their growth. They are still in the same state, no signs of growth. They don't seem to be dead, but they are just not growing. Currently it is about 50 of my first 80 grafts. Honestly I don't believe they will start growing
I am switching now to grafting to younger pereskiopsis in hopes for better results.

That's some pretty serious growth for only 2 weeks..

Give the other one's a couple more week is my vote.

I think if they should have started growing again, it wouldn't be by the same time for all of them. If they are supposed to renew their growth, some should do it soon. They will get another week or so, but if none of them shows the willingness to thrive, the rootstocks will be cut. With regrets though

If you see a tiny wet spot when you pop your scion off... your connection was good and your graft would have grown given enough time, albeit it might have continued to be painstakingly slow compared to your other grafts for a bit.

Always remember though, you can graft a side shoot or areole from your stock when you have a scion that is growing excessively slow like this and still get good use out of the stock. Once the smaller scion is growing faster you may decide to remove it and graft to another stock or simply leave it be and see if you can get two scions growing to a good size on the same stock.

Good point Wakinyan!
I have never done the grafting onto areole, so would rather prefer grafting onto the side shoot. I will consider it.

So what do you think, will those slow-growers ever grow as fast as their faster brothers, or are they going to grow so slow forever? I don't have problem to wait for them to take off, but only if they have any chance to catch up with others later on.

It is like having two children. One child is a head taller than the other one, but the other child will eventually hit its growth spurt as well. The one that is ahead taller however will likely keep that advantage for some time however it generally becomes much less noticeable over the period of 7-8 months. As with everything though, you begin to develop an eye for these sorts of things and you may indeed wish to re-graft some of the smaller seedlings when they get a smidgen larger and have enough tissue to enable you to do so without losing that genetic material.

Current state :
first section (80 grafts) : 30 actively growing, 48 stagnating, 2 dead (smashed).
second section (80 grafts) : 50 actively growing, 30 stagnating

Those stagnating from these sections are let to grow off shoots, where another seedling will be grafted. They are not loking dead, they are just not growing. Weird. I am curious whether at least some of them will ever grow.

another 2 sections (2x80) are grafted
another 2 sections (2x80) are waiting for grafting

few pics (age 13-19 days)...

Looking good.

The reason some of them might not be growing is because your allowing them to grow offshoots... The plant just wants to grow, it doesn't care how, and it's going to take the path of least resistance.

They haven't been growing till now, so I let one off shoot per rootstock as Wakinyan suggested. I understand that the life energy pressure can decrease for current scions, but they've got a chance and they still have some. This is a nature, the one who's growing wins.

I could have tried grafting to the areole for some of the rootstocks, but this is a new technique to me and I am not sure what can be the success-rate.

I'm betting those offshoot grafts grow and the ones that stagnated giving you more actively growing scions than you have root stock.

As for the areole grafting... it is just as easy. Most fail at areole grafting because they fail to try until they realize it is just as easy as any other grafting.

Great work my friend. Keep it up. You already look like you have been grafting for years.

Thanks Wakinyan, I wouldn't have such results without some very kind and knowledgeable people here
Although I can say my take rate is almost 100%, I am looking rather for "grow rate", and here I have only about 50%. I am trying to identify the problems and correct them, but hard to say whether the identification is right.
The reasons I see are :

1. The pereskiopsis is not "juicy", because it was too tall and 2/3 had to be cut off. Now I am trying to use younger stock, so only about 1/5 or 1/4 of top is cut off.

2. I pulled too much when applying the parafilm. In fact it is not necessary and is much better when not using so much power, as the scion is not turning over or leaning so easily. I bet many of those stagnating cactuses are not properly connected with the vascular bundle because of this.

3. I am trying to do perfect cut of the seedling, so it is not tall and it can stand straight. Any imperfect cut leads to higher possibility of scion leaning or turning over.

I can't afford waiting months before those grafts will start growing, with my limited space. So I think I will give it a try and do some grafts onto areoles. Let's start with one tray and we will see how it goes...

Well, the tray(20 containers) has been grafted using the areoles. To be honest, I don't think it is as easy as grafting onto the top of the pereskiopsis. The search for ideal spot is much more difficult, because the vascular ring is not very visible here. I am not sure whether I saw it at all. Maybe I was doing something wrong, I didn't find any directions how to do the cut, or how deep it should be, so maybe this may be the problem. It was rather quessing where to put the scion than knowing it exactly.
Firts 10 grafts were done this way but then I noticed shiny dots appearing shortly after the cut. Yes, there were some tiny drops of liquid flowing out of the tissue. So I simply put the scion onto this spot.

Nevermind, I will give it a week or two and see whether any of the scions have taken. The original grafts are still on the same rootstock, so they still have some chance to take off!

Just some tips for pereskiopsis growing...
Yellowing leaves are showing too much water, at least in some cases. Another sign can be drooping leaves. And finally, for indoor growing, if you see those small flies, clear sign of too much water too.
I am bottom watering my peres and though it can withstand more water when root system is properly developped, it doesn't like standing in water. My watering cycle seems to be ideally 3-4 days. It is not fully dry when watering, but most of the water is away and the containers are fairly light.

I can 100% assure you that grafting to areoles can indeed be so easy it will make your head spin. Seeing as you have already mastered the other easy technique and are working at improving it... the least I could do was add some more pictures to help you on your journey Pete666.

To get you started... I have added some more pictures to an old thread. I will go home and see what seedlings I have to do grafts with if the light freeze we had didn't take them out and see what grafts I can do to illustrate this technique better for you though. https://www.dmt-nexus.me...osts&m=921141#921141

Thanks Wakinyan, perfect would be a close image of the cut, so I can see how to do it. And positioning of small seedling is important too, because my seedlings are really small and there is many possible spots on the cut where it can be positioned. I am scanning your mentioned thread, so if you put the pictures there, I won't miss them.
The thread is awesome, you are really a grafting master!

Close up of the cut and positioning for your thread my friend.

Yes, now I better understand what this kind of grafting is about. I will try few cuts before real grafting and will find the ring first. Once I have the right cut and the ring, it should be similar to what I know.

Once again thanks Wakinyan, your experience is gold!

Some update...
Third section has given me 60 growing, 20 stagnating grafts. This is quite acceptable ratio, although nothing near to 99%. But this is a first year, it would be a bit boring and demotivating to be pro after so few grafts
I have grafted one whole section (80 grafts) to younger pereskiopsis, just rooted. Currently it doesn't look like anything special, it has about 53/80 growing scions. But some still may join this group, although I doubt it is gonna be over 60/80.
Next I have grafted two trays to young off shoots of older pereskiopsis. Still waiting for results.
Next grafting was two trays of "areole" grafting, which was not real areole grafting, as I was not cutting the rootstock correctly. Wakinyan showed me how to lead the cut and I have first tray(20 grafts) done by this technique and waiting for results. I hope this is going to work, as it seems to be a bit less work than grafting to top and more grafts can be grafted to one stock.
I have screwed two trays of rooting pereskiopsis, too much water killed most of them. So had to source another 50 pcs from ebay. Rooting or not fully rooted pereskiopsis needs much less water than properly rooted.
And those stagnating grafts....few started to grow, but after about 14 days it is only about 3 of 60 grafts, which is not very positive and is not worth waiting. If most of the grafts are already growing and getting fat, those stagnating should be grafted again without delays, maybe leaving the graft and using areaole grafting.
Some pictures ....