With most types of plants (not cannabis) you cut the stem about 10mm below a leaf node. The node is the fatter bit on the stem where the leaves come out. Most plants produces leaves or roots at the nodes.
Cannabis plants will produce leaves at the nodes but can produce roots at the nodes and also on the straight part of the stem. So for cannabis you can cut the stem anywhere and they develop roots on any part that gets wet.
You don’t have to cut on an angle or anything weird. Just use a clean pair of sharp scissors and cut it at a 90 degree angle to the stem (straight across). If you are taking cuttings from different plants, sterilise the scissors between plants so you don’t transfer viruses, bacteria or fungus from one plant to the other. Plants can carry these diseases and not show symptoms so use some 60% alcohol on a tissue and wipe the blades between plants.
Cuttings should be put into a container of water straight away and left there for 15-30 minutes before dipping in a cloning liquid or gel and put into a seed raising mix or aeroponics cloner. Remove the lower leaves so 3-4 inches of stem is free of leaves. Dip the bottom 1-2 inches of the stem into the cloning gel or powder and then put the cutting into the cloner or potting mix. With aeroponic cloners, put the foam collar about 2 inches above the base of the cutting. You want about 2 inches of stem under the foam collar and the roots will grow on that 2 inch section.
I use a 1/4 strength liquid fertiliser in the aeroponics cloner. The spraybar in the cloner will wash off most of the cloning gel but i still use the cloning gel as well.
I don’t use a cover on the aeroponic cloner. The plants generally don’t need it and if they start to wild, i make sure the spray bar is working properly and if it is, I use a spray bottle with tap water and spray the leaves a couple of times a day for a few days (until they stop wilting).
Under good conditions, cuttings will have a decent root system in 2 weeks and should be planted up then.
The reason people cut the leaves is to reduce the area the plant loses moisture from. It’s not necessary if the cutting is in water (like in a cloner). If you are putting cuttings into a seed raising mix or potting mix and it only has a couple of leaves, you don’t need to trim them. If the cutting has lots of leaves you can remove some of the lower leaves, which is preferable to cutting the leaves in half.
This is a tip for taking cuttings from any type of plant.
The parent plant should be watered and fertilised regularly for at least 2 weeks (preferably a month or more) before taking cuttings. If you take cuttings from plants that haven’t been watered for a while, they will be suffering from drought stress and the cuttings usually fail.
In addition to that, try to water the plant a couple of hours before taking the cuttings. This allows the plant time to suck up a heap of water and nutrients and put it in the leaves and stems. When you take the cutting a few hours later the cuttings have the nutrients and water in them and will do better than cuttings taken from a dry plant.
