rooting japanese black pine from cuttings

Discussion in 'Grafting, layering & propogating' started by Graydon, Jan 21, 2007.

  1. Graydon

    Graydon Chumono

    I'm going to try some cuttings. There is so little information available out there I thought this may make a good thread. My interest in this piqued when I received a couple of rooted cuttings from Brent at Evergreen Gardenworks. One is "hachi gen" and the other is "mi nishiki". The cool thing with cutting grown p. thunbergii is that if the cultivar is a nishiki the corking will be present on the roots. My more advanced nishiki are grafted and they all have some sort of ugliness in the transition to the rootstock. There are workarounds but they are all weak solutions in my opinion.

    I understand I need bottom heat and top mist. I have a handle on when I should do this in my area (perhaps February) and I have some stock on my benches that can provide me with some limited cutting material as well. I know I need a strong hormone to induce the roots. That's it - that's all I know.

    Here are points I am pondering :

    1. Bottom heat - I have been looking at heat pads for a while. My latest concept are some non commercial units roughly 20" x 48" typically used for seed starting. I have also looked at a thermostat unit with a temperature probe so I can keep these mats at the proper temperature. I would think somewhere in the 75 to 85 degree range would be good. But again - I have no idea.

    2. Top mist - my mist system could use some refinement. It consists of a faucet timer, some plastic tubing and several hose end misters made by Dramm. The misters work well and do produce a nice mist but I will need to dial in the frequency of the misting so I will need to refine this system with a timer and valve approach. I should point out I don't have a mist house - it's all in the open in a shady area. I guess I need to consider building a small mist house area. More like a mist "box" as I have no room for a hoop house.

    3. Sterile soil and pots - My plan would be to continue to use a soil that I already know and use. I know the pines I have love the akadama, pumice and sometimes lava mix I currently use. I know the akadama will go for a year or so before the breakdown begins. If I could just get a coarse sand I would be happy. I would think small pots in flats would be the way to go so the newly emerging roots don't begin to tangle over the first year in development.

    4. Cutting size and needle amount - I am assuming I can go for much bigger cuttings than I have tried in the past. My prior cuttings were basically large scion size. Last years wood or newer. Having never seen this before I had no idea what to do. Then I saw one of Lindsay Farr's World of Bonsai, episode 8 that shows a grower in Japan, Toshifumi Obitsu. He was speaking in a greenhouse and points out his Kuromatsu cuttings from big plants. Bingo! (See attached screen shots). It appears to be a little bigger than what I tried and most seem to have terminal buds. Can't really see the diameter of the cuttings.

    5. Hormone strength - the strongest hormone I have is Hormex #8 (.8% IBA) and I suspect this is not strong enough to induce roots on older wood. According to the Wikipedia IBA should be dissolved in alcohol and then diluted with distilled water for use. Good thing there is a chemical testing lab next door to my shop and they would be happy to help me mix to a proper dilution. So how strong should it be? Would a several second dip be better than the wet and dust method typically used with the powdered hormone?

    6. Aftercare - common sense tells me to keep them under shade cloth to minimize the amount of direct sun on the needles and to minimize transpiration. I would assume that if a cutting takes they will need this care for up to a year before being slowly moved to a sunny environment.

    Hopefully this will generate some good conversation - at least from those of us who enjoy the process of plant propagation.

    Yes - I am possessed with JBP propagation. Could be worse. I figure I have 20 or so years before I won't want to do this anymore. I hope to be able to churn out material for some younger people to take to the next step over the next 50 years. Grand but somewhat noble dreams for sure.

    Thanks in advance for the input.

    Attached Files:

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  3. Brent

    Brent Mame


    It's not easy, and it takes a lot of experimentation for adjust for your climate, materials, situation, etc, but it definitely can be done for some cultivars of Pinus thunbergii:

    Bottom heat: yes, almost essential, 75 to 85F is about right, day and night. Propagation mats are easy, but can be expensive to run. Having warm Florida days and nights will help keep the cost down.

    Mist: Probably the most critical element. Buy commercial greenhouse mist heads that are made to do the job. I use expensive Floramist brass heads, but many good plastic ones are available now. You can find them at and Tek Supply is a wonderful resource for greenhouse materials and substantially cheaper than all the others. The timer is best from Charleys, Tek doesn't have one that is variable enough. You want an 'on' period range of 5 to 30 seconds (or more), and an 'off' range of 5 minutes or more. It takes a lot of playing around to get the combination right. Ideally, you want the mist to come on just as the last of the surface water is evaporating. This depends a good deal on the environment and mist density. My typical period is 7 seconds 'on' and 9 minutes 'off'. Last season, I added a humidistat to the system as well and had the best crop of cuttings in my twenty year experience (but then I live in a semi arid region with very low humidity). This is a separate system of foggers designed to keep the humidity at about 60% independent of the mist coverage. The fogger nozzles are also available from the above suppliers. The humidistat controller is from Tek, but you need a special electric valve designed to work at extremely low water volume, this you get from Charleys (1/4 inch solenoid, positive action closure). The foggers you string along the ridge of the structure. You may or may not need active cooling in Florida, it should stay below 100F inside, you can use an inexpensive evaporative cooler to do this. Tek has very inexpensive thermostats to actuate this unit.

    The real trick is to keep the tops of the cuttings continually moist without saturating the medium, which will quickly rot the base of the cutting. This is where the bottom heat comes in, since it is an active element in reducing moisture in the medium.

    Soil and Pots: I use perlite and peat (about 16 to 1), but some experimentation might be used here. I think the calcined materials, turface or akadama might make an excellent substrate. I would still use a bit of peat since it has a demonstarted ability to stimulate rooting in some species. Flats or pots should be deep enough that the saturated layer of medium at the bottom is nowhere near the base of the cutting.

    Cutting Size: A single unbranched shoot is probably going to work best, material just slightly larger than a scion. I'm guessing, but I don't think wood older than one node is going to work.

    Hormone Strength: I have done a lot of experimentation here, and without going into all the trials, I have found 3% IBA in a talc to be the only reliable hormone. If you can obtain some crystaline IBA, you can make your own mix with any ordinary talc (if you can stand the baby powder smell). It 3% by weight, so you will need a pretty good balance. You may need a small wooden ball mill to get a good mix and pulverization. Rock tumblers are perfect.

    Shade and Aftercare: The whole process should take place under 50% direct sunlight (50% shadecloth). This is another point that is not in dispute and I have researched this carefully. Each cutting will have one to a half dozen roots that are thick, coarse, and only slight branched in the first year and are extremely easy to transplant. Normal cutting care (50% shade) for a couple of years is necessary for me, you may be able to get them in sun sooner, but don't push it, they are perfectly happy with this level of shade.

    see our blog at
  4. Graydon

    Graydon Chumono

    Well thanks Brent! I thought you may still be on "holiday" and not catch this for a while.

    That's a lot of info to digest in depth. I will read it several times and try to absorb it. Some is as I suspected (based on my prior failures) and some info is new to me. The misting info was of much help.

    I have a couple of p. thunbergii "nishiki nee" that look to be the same cultivar as the "mi nishiki" cutting I got from you this past year. Both have butchered graft unions so I will give them a try. I can't see a difference between them and the "mi nishiki" as they are budding out. Could be close or could be the same - you never know based on where I got them.

    By the way is was a treat to meet you at Schley's and have a chance to chat. I'm going to stay on Jason to work up a deal on those ilex and try to get Walter in to do a workshop. Great idea - now we need to do the follow-thru.
  5. Smoke

    Smoke Imperial Masterpiece

    Fresno, CA
    Brent, I was wondering about your take on Pine candle cuttings? I have seen pines propagated by useing candles cut off and struck. Have you ever tried this?

  6. Brent

    Brent Mame


    Yes, I have tried it. I have yet to get a candle to root. I guess it can be done, but mine always rot. I use one year old wood.

  7. Graydon

    Graydon Chumono

    OK Brent - I have absorbed the info. Thanks again for the sources. I currently order from Charley's and for some reason got a Tek Supply catalog at my office.

    I have a plan in place and will soon order the mister parts and bottom heat pad with thermostat. I'm also getting some shade cloth to make a small shade bench. I don't have the room for an entire house but I can give up a good sized bench for propagation (especially after I cull a bunch of plants with no potential). My idea is to build a frame, cover it with the shade cloth and then cover with a clear plastic for now to keep the humidity up - remove it when the time comes leaving just the shade.

    The only issue I am having is finding a good source for IBA. The only legit supplier I have found so far is and I can't purchase from them without the "proper" business license. I found a Canadian source at, they seem to be a "snake oil" type site but we'll see what I get.

    The talc part was easy - I use pure talc in fiberglass fabrication and it has no scent. Let me know if you want some, I have more than I can ever use now that I don't do much fiberglass fabrication.

    I suppose if I get real serious about this I need to come to see you, spend some time doing grunt labor around your place and see in person what you have going on with the cuttings.

    The last batch I tried was from October and November. They are at a local nursery in the mist house so I don't have daily access (that's a good thing) but I was out there last Monday and took a peek. One was "nishiki nee" and the other slips my mind right now. Each one has 24 cuttings. Roughly half of each had turned brown, perhaps due to sticking too deep (oops!) but the remaining ones were nice and green. I figured no loss if I check them out so I started carefully pulling cuttings. No roots at all but all of the remaining ones had developed a very nice callus at the cut. The stems were firm (no rot) and the needles were also tight and firm. Perhaps these are taking off slower based on pre winter cutting and not post winter cutting. I culled some of the better ones and re-applied the strongest hormone I have - .8% IBA. I'm not hoping for anything at this point with these. At least the ones not stuck too deep are still green and callused. I can hope that if I have a stronger hormone and more consistent mist I may have a handle on this.

    Thanks again Brent !
  8. Graydon

    Graydon Chumono

    My shipment of IBA arrived today. Not what I was expecting but in a good way. It's labeled as 98.5% IBA and it's in a powdered form. I can assume the missing 1.5% are inert ingredients..?

    25 grams is a lot more than I expected. If my math is right I will be making 833 grams or 1.836 lbs. of my mix. Perhaps I should do smaller batches.

    Next step is to cut to a 3% mixture by weight. Good thing there is a lab next door as I don't think my digital scale is good enough for this.

    Contact info is on the letter that came with the IBA in case anyone needs some.

    Attached Files:

  9. Bonsai Nut

    Bonsai Nut Administrator Staff Member

    OC, CA
    I'm curious why you didn't just buy a pound of Hormex #30? (Assuming your method must be cheaper)

    Why 3%? I didn't think you needed to go that strong with black pine. Do you have a reference you could share? (I'm curious - I've got an airlayer attempt coming up and I have never used anything stronger than 1.6%)
  10. Graydon

    Graydon Chumono

    See post #2 above as to why.

    Tried to find Hormex #30 local (no luck) and internet (no luck - the sellers I found were out of stock).

    Yes, cheaper but also gives me the option to make any concentration needed in the future. Roughly $35 for IBA and I have the plain talc at work for free. Hormex #30 is roughly $100 plus shipping per pound. If I do all at 30% I will have like $40 in almost 2 pounds. So yes - cheaper by far.
  11. Brent

    Brent Mame

    Hormex (allegedly) stopped making Hormex 30 in one pound packages several years ago. You could still find the little Harry Homeowner kits of one ounce of 16, 30, and 45 for awhile, but even they are getting difficult to find. Graydon, I will take the excess 3% talc mix off your hands, or at least part of it. I would like to get started on pine cuttings again, and my supply is nearly gone. It actually takes a good deal of the mix to treat the pines since so much sticks to those rough stems.

  12. wahoo172

    wahoo172 Yamadori

    Lakeland, Florida
    meth lab?

    Kiddin i know it's a testing lab
  13. Tachigi

    Tachigi Omono

    OK, I is a bit confused, is this Hormex 30 not the same product in 1 lb containers?
  14. Brent

    Brent Mame


    That's it alright, maybe they are making it again, maybe they haven't changed their website in five years, I don't know. I do know that about six or seven years ago when I last tried to get Hormex 30 in one pound container size, it was virtually impossible, and every supplier I talked to said it was discontinued. My friend and I bought out the last 3 pounds from a large greenhouse supply and I have been living off of it ever since. The real test is if you can find a distributor that actually has it for sale.

  15. Graydon

    Graydon Chumono

    It's almost time for me to start the cuttings. Actually it may be a bit late but I'm going for it soon. Need to find some time to assemble the misting system and control unit as well as redo my main irrigation system with a real timer. I may be doing this after dark with worklights (neighbors may not be happy but...).

    Made the 3% hormone cut this week. My little 25 gram package of IBA made a lot of hormone mix when cut with pure talc.

    I'll try to do a nice little photo essay of the process of cuttings from start to in the pots. Perhaps then I will know what I did wrong...
    Last edited: Mar 4, 2007
  16. grog

    grog Shohin

    Optimism! Now that's what I like to hear. :D
  17. Graydon

    Graydon Chumono

    sometimes even a blind squirrel finds a nut...

    Roughly a year ago I did some major nishiki pruning at the nursery where our club does monthly workshops. I decided to take the drop and try to root them using hormone I had on hand (0.8 % IBA). Please note that I did this prior to starting this thread this year.

    They went in to a mixture she had on hand and I added a bit of akadama to make it drain a bit better. Over the past year I had been keeping an eye on them and out of 60 cuttings at least 24 had turned brown. Two weeks ago I decided that even though the remaining ones were still green that it was a failure and to pull them so she would have more space in her mist house. I sorted thru one flat of cuttings hoping to find a root. Nothing. I was almost ready to dump the second flat in the dumpster but decided to look at them as well. The last one I pulled had roots. I nearly yelled for joy. It had 5 or 6 non branched but healthy white roots coming from just above the cut. I didn't have the camera so I quickly potted it back up in a fine akadama, pumice and lava mix I had.

    The down side is that I have no idea what cultivar it was as each flat was tagged but the tags were pulled and thrown away before I found the one good one. It really does not matter as this is just proof of concept for me.

    Below are photos, nothing much to see. The terminal bud has begun to move up and out a bit and one new bud has pushed thru the bark on the side. It's home now in a somewhat shady spot getting watered 2 times a day as needed. I added some organic food and also feed it with 20-20-20 water soluble chemical stuff.

    Now I feel much better that this coming spring I can do a hundred of these under better mist with bottom heat and be successful.
    Last edited: May 17, 2009
  18. irene_b

    irene_b Omono

    I ordered from Hormex without a problem.
    Contact person is: Wanda Walk

    Last edited: Jul 7, 2007
  19. Brent

    Brent Mame

    Congratulations Graydon, now your hooked!

  20. Michael Milligan

    Michael Milligan Sapling

    I glad to finally hear that you did it... even if just one took. If it can be done, then it can be done well. Like in most things, a little practice and you'll have it down cold.

    Are you at all worried that your hormone mix might be too strong and "cook" the cutting?
  21. Graydon

    Graydon Chumono

    According to Brent and some research I have read online it takes a strong hormone to induce the rooting on these pines so no concern on too strong. I was shocked that one struck with 0.8% before I found out about the 3.0%.

    I did replace the almost failed cuttings with a tray of new ones that were dipped in the 3.0% just to see if it can happen again. Her mist system is less than desirable and has no bottom heat but you never know.

    I'm hooked alright and can't wait until this winter to get my cuttings going under good mist with bottom heat.

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