When I first started taking my own cuttings I would have a very mixed success - sometimes I would get great results, then other times I would get no result at all. On occasions things would be taking weeks and weeks to root, and I would end up throwing them in the bin as my patience waned, and then low and behold, a week later and an accidental glance in the bin the cuttings have taken root!
Like any other area of growing, there isn't one correct way to manage this unpredictability but, learning from trial and error along the way, I have developed a proven, trusted technique.
Starting off with equipment, I use a Garland XL propagator. This allows me to get a tray of seventy two cuttings cubes inside easily, with space spare for airflow. I also use a heat mat. You can of course use a Garland heated propagator. Neither is better than the other, its a simple matter of preference.
Then I take some tiles - bathroom tiles, kitchen tiles, it doesn't matter - and I put them in the base of the propagator. I won't completely fill the base, leaving of a gap of maybe two inches all the way around the edges. This helps excess heat to escape. I let this gap fill with water, which creates condensation on the lid when in contact with the heat.
I use Jiffy peat pellets for growing medium, mainly to ensure a sterile environment, but again, its mainly a preference thing. I lay the pellets heads up in a separate tray and add five litres of water to pre-soak the pellets. Remember, this 5 litres is for seventy two cuttings, so adjust accordingly to your needs. The water should be warm with rooting products already added. Having warm water simply makes the peat balls expand quicker, and it is a case of more the merrier with rooting products - be it Mycorrhizae, Rhizotonic or root accelerator. When the pellets have soaked up the water and are expanded, give the pellets a squeeze out - we don't want to wet the cuttings when they are added, avoiding the possibility of stem rot. Then shape the pellets and sit them on the tiles in the propagator.
Now it is time to take your cuttings. When taking cuttings from the mother plant I will only take cuttings from the top of the plant. Books generaly recommend taking from the bottom of the plant but I find this is only really suited to plants grown from seed, as it only really works well with first generation cuttings. I look for a head, and I want a head with two nodes. I’ll leave a node down, which I’m going to lose, what I’m going to cut off below. See Diagram 1 to illustrate what I mean. The diagram also shows the size of cutting I am looking for. Some people take much smaller cuttings but I choose this size because, if done correctly, there is little difference and it saves time. I will do this for a good 30 to 60 cuttings, collecting them into a jug. As a footnote, always take more cuttings than you need, for obvious reasons.
On a work surface, get a sharp scalpel and one by one cut the cutting at a 45 degree angle, about two centimetres below a node, and then grabbing the node, strip it down. Remove any big leaves, and cut back the top leaves. The reason for removing these leaves is to cut down on the cuttings workload, saving its energies for rooting. Remember, having cuttings taken is a very unnatural thing for a plant - the natural thing for a plant is to seed - so minimising stress as much as possible is prudent. Put the cuttings in the pre-soaked and drained cubes, not forgetting to spike a hole, not much bigger than the stalk, as this will stop the cuttings from falling over.
Now the cuttings are planted in the propagator, one thing we should mention is the vents. Some people will find this strange but I leave my vents open 100% of the time. I do this because achieving perfect airflow is very difficult and with the vents always open we are constantly getting new air, circulation, and a generally pleasant environment anyway. To help this freshening of air I like to take the lid completely off for half an hour every day if possible.
Common advice is to spray your cuttings every day. I do not follow this advice. The water we have evaporating at the bottom of the tray is sufficient to keep humidity. The only time I spray is when I’ve taken the cutting. I find that any more spraying just prolongs the time before the cutting takes root, because you are feeding that cuttings through their leaves. Why would it root? Basically, you are forcing the plant to act by not spraying. It has the added bonus of cutting out the chance of stem rot.
When the cuttings start to root, usually 7-10 days after planting, we’re ready for the next process, to move the cuttings into their pots. However, there is a big factor that is often overlooked at this stage - dramatic humidity change. The cutting has been in the propagator for 7-10 days, with anywhere between 90-100% humidity. If you simply take the cutting out and put it in a pot, that cutting is simply going to go “Uhhh… excuse me?! I can’t handle this, I’ve just had 100% humidity”, no matter what humidity you have managed to achieve in the room.
To stop the cuttings experiencing this acute stress I put them into another propagator with conditions somewhere between the two environments - a kind of halfway house. This propagator will be exactly the same, but without the tiles. Of course, rarely does a tray of cuttings all root at the same time. You can wait until they’re all rooted and move them together, but personally, I like to get a cutting out into another space once it's rooted. This means you have more control as the plants develop at different rates.
Don't worry if you only have one propagator though. Waiting until all the plants have rooted is still acceptable. A tip if you are in this position and are getting a little bit impatient, is to wait until 75-80% of the tray is rooted, and start the hardening off process anyway. By the end of the hardening off process, the whole tray has rooted and it’s not a problem. The ones that do drop are not the ones you wanted anyway because they obviously didn’t have the vigour to finish in line with all the others.
A final great tip for making the hardening off process more successful is to manage a gradual change of humidity by using the lid. From its standard position on top of the tray which is achieving 100% humidity, lean the lid and prop it open so it is 20-25 degrees from the tray. This air gap will take the cuttings down to maybe 50-70% humidity, bringing it in line with what you may have in your room. Do this for 24 hours then start taking the lid off for increasingly amount of times - firstly for half an hour, then perhaps an hour, then perhaps two. At the end of this process I sometimes even take the lid off and jack it up on one side so there’s even more air going into it. This gives the plant as good a chance as possible to be able to handle the harsh environment of being transferred in its pot.
I hope you have found this article useful and you decide to follow some of my pointers. I have made thousands upon thousands of cuttings, giving many away, and take pride in the fact that nobody has ever reported that any have died in their pots. If you follow these simple instructions you'll be achieving that sort of success in no time at all.