Hot Callus Pipe DIY


Hot Callus Pipe DIY
credit: Ryan Russell

A friend emailed this PDF to me. He’s done a lot of grafts on his already with super takes. He waxes or parafilms the scion and the union and he wraps the roots in moist paper towels and bags them. 21 days on the pipe. [Hot pipe DIY propagation method and grafting techniques. Hot pipe DIY propagation method and grafting techniques.pdf (4.1 MB)

You’ll see he has his own grafting technique. It’s pretty slick! There are photos showing a lot of exposed tissue but when I asked if that is typical he said definitely not. He wanted to emphasize how the green ribbon of cambium matched so well on his scion and rootstock and I’ll assume that was his best example. He’s giving a grafting seminar and that PDF is for the people showing up.

The foam pipe would be better if 2" wide. His is 1.5 but said 2 would be better.

Back to the photos I’m talking of, you’ll see two side by side and the bark is different. The one on the right is a healed version of the one of the left where all that open tissue callused over. They’re identical in craftsmanship but are two different plants.

The heating element and cable I found on Amazon for 40$ and it’s already assembled. My friend paid 4$ a foot for the cable alone at his local Ace. This is a great deal. You can buy them in 4’, 6’, then they skip over 8’ and go to 10’ and I wouldn’t doubt if they go even further. I’m going to use a 2 x 4 x 8’. My bud said to cut the foam every inch. His photo shows further than in inch. He said an inch is great. He’s built a few of these so he’s changed it up. He said you can get 90 grafts on an 8’ system. Isn’t this great?

Heat Tape Easy Heat Freeze Protection Cable Waterline Heater Pre-cut to 10 Foot includes Installed Plug Head - -

This is a must for many of us and it’s affordable and it works effortlessly. Especially for more difficult to graft hardwoods. Hot callus grafting was designed for hardwood plants notoriously known to be difficult to graft. The built in thermostat heats the cable at 84F / 29C.


Certainly you can do chip budding or whichever technique you do best. If you do not know already, scions or budding material + rootstock are always dormant. You can do them bareroot or potted. It doesn’t matter.

A cool basement or similar is what they need. Not a warm greenhouse. I’ve my board on my basement floor already. Total cost for me 39$ for heating element & cable; 3$ for foam pipe insulation and I had a 2 x 4 x 8 and electrical staples so a grand total of 42$ or appx. 50$ if you haven’t the materials.



Thanks Dax, I’ve been thinking of building one of these but it’s hard to find a how to.


Thanks Dax- this looks less complex to build than others I have seen. What types of varieties do you intend to graft using this? I’ve read it is good for nut trees and other more difficult to graft trees.


Ingenious, practical, affordable, straightfoward, simple, doable- just about perfect. Makes me want to buy a bunch of rootstock and get started!


Is this beneficial at all for easier to graft varieties, like apples/pears? any risk of the pipe getting too hot and cooking the grafts?


It makes life simple Derek and that’s what we all want \We became the weather person. I’ve never used one but have stood right over one and looked how complex and expensive it was.

J, I’m going to graft a lot of bareroot trees with it in the future. Nut trees, persimmons, pawpaws, oaks, beech, and anything in my six acre arboretum I have scionwood for. Gosh, I have no idea what I’m going to do.

Think of all the less work/cost involved everyone. You can order 90 bareroot rootstocks at a time/shipping is cheap/Not as much potting mix is necessary or pots/you can stick them in a couple buckets to carry them to the field already healed. Gosh, it’s probably endless compared to what many of us have been doing.

Want a side business in zone 3 grafting pecan trees you can now do it. Buy rootstocks and scionwood and have at it.



Hey Dak, when you graft oaks and nuts with a hot callus pipe do you let the rootstock begin to wake up or do it fully dormant?


You can do it either way, Roy. You should also be able to graft on rootstocks that have pushed where it would be more like bench grafting.



I went with a 1 x 4 x 10. I like it. An additional less than 5-bucks to get the board and utilize the entire ten feet of cable I purchased.

Hope you all are up and running soon.



That looks awesome Dax, keep us updated on how well it works!


I’ve been meaning to build such a device in anticipation of my persimmon rootstock arriving.

I couldn’t find any reference that this keeps the temps at 70F. All I know is it avoids freezing. How do you keep the temperature stable around 70?


I encountered the exact same issue as ramv does. I was only able to find themostates that start heating when temp drops below 3°C and stops when temp reaches 10°C. Maybe you manipulate it to run nonstop and then it doesn’t get hotter than 21°C? Other than that I really like that setup.

I was thinking about using a soilheater for fish tanks on a timer but I am not sure you can safely use them in a dry environment.



Guys my buddy’s been using it for two years. I asked him the temperature and it’s 70 F / 21 C. There are no questions about it.

Kindest regards,



I don’t question it. I just have to find something appropriate available over here. Did a search on and couldn’t find a similar thermostate thats turning the heating cable on at temps above 10°C. I don’t have a room cold like that. I am sure it works fine with the right thermostate.

Is the thermostate you use heating nonstop when plugged in?


Yes it is heating non-stop.

I went and checked the temperature and he’s wrong. It’s 84.2 F / 29 C. I put my finger on it and it’s too hot. Which worried me. So I quickly looked at all the grafts that I thought I had pressed onto the cable but 30 of 33 weren’t near the cable but easily 1/4" / 7mm above. Those other three were pretty close but still not on it.

I can tell you it works excellent. I would suggest to everyone to put the union in a slot and be sure it’s above the cable. That’s all that’s necessary.

My apologies to everyone.



Thank you, thats all I need to know. I really appreciate your valuable input. Its a simple but (therefore) genius setup.


You are very welcome.


Something like this might work better?
[](http://Gro quick cable)


I don’t know. I’m not going to change anything. The way I see the ambient heat produced with the current system I have (inside the tube) is absolutely perfect.

My friend has taken hundreds and hundreds of grafts off his and is extremely happy.



If I start my trees mid winter do you think it would be ok to heel them in outdoors afterwards and cover them? Not sure how to store my grafts and keep them dormant after grafting, I do have a beer fridge in the garage I could use lol. I already have figs I have to baby when they start breaking dormancy, I hate to add to the list!