Generally, spring and summer are the best times to take leaf cuttings i.e. when the plants are at their peak.
If sufficient warmth, moisture and humidity is provided, leaf cuttings can be taken at any time of the year, although it may take a bit longer for new plants to form in autumn and winter due to low light levels.
Not all plants are suitable, but many are, including;
Begonia, Crassula, Echeveria, Peperomia, Sanseviera, Saintpaulia, Sedum, Sinningia, Streptocarpus.
An electric propagator is best, but you can use pots or trays placed inside a polythene bag and place them where they will get sufficient heat to root.
A sharp craft knife / razor blade, for detaching and /or cutting leaves.
Compost should be an equal amount (by volume) of peat and sharp sand.
Hormone rooting powder.(ensure it is within its use by date)
Support canes or wire to keep the bag off the cuttings if using plastic bags as a propagator.
The exact rooting method can vary according to the type of plant, for example;
Saintpaulia (African Violets):
Cut African Violets with their stalks attached, shortening the stems to 50mm (2”) long*.
* This is the same principle as taking a leafbud cutting (see here)
Dip the cut end into hormone rooting powder.
Using a dibber, make a hole in the compost at a 45° angle, to help support the leaf, and insert the entire stalk, then firm the compost.
Several leaves can be placed in one pot, providing they don't touch one another.
When supplied with moisture, high humidity and a temperature of 16°-21°C (60°-70°F), the leaves will root and form new plants from the leaf base.
New plants will grow from the base of the cutting, and the original leaf will wither away.
Eventually, these young plants can be potted up and treated as the parent plant.
An alternative method is to stretch cling film over a water-filled jar, securing the film around the rim of the jar with an elastic band to keep it taut.
Pierce holes in the cling film and insert the leaf stalks through the holes sufficiently far down as to allow the leaf stem to be immersed in the water.
Ensure the leaves themselves are kept dry.
The leaves will eventually send out roots and form new plants.
*Do not use hormone rooting powder when adopting this method!
Select a fresh mature begonia leaf (1), sever it from the parent plant with 25mm (1”) of stalk attached.
Turn the leaf over (underside up), make several 10-12mm slits just below where the main veins branch (2).
Turn the leaf over and lay it flat, ensuring that the underside of the leaf is in full contact with the damp compost (3).
Place small pebbles on top of the leaves to ensure the leaf is in contact with the compost.
New plants will grow from each slit.
1) Select leaf
2) Slit veins on underside
3) Top Surface
Alternatively, cut the leaves into small squares or triangles so that each contains a section of main vein.
The pieces of leaf can then be inserted into the compost,again like a leafbud cutting, or just simply rested on the compost face up.
New plants will grow from each piece.
The long narrow leaves (1) of Streptocarpus are cut crossways into several sections of approx. 50mm (2”) long (2) and inserted in the compost (3).
Ensure that the cuttings are inserted the correct way up, i.e. insert bottom of cut into compost.
New growths will emanate from each of the veins as the main leaf withers.
An alternative method, is to cut the leaf along its central vein (4) and insert the two pieces (cut side down) into the compost.
1) Select Leaf
2) Cut into Sections
4) Cut length ways
Sansievera, Saintpaulia,and Sinningia can be propagated in the same manner!
Crassula, Echeveria and Sedum are prone to rotting.
To avoid this, leave the cuttings to dry for a few days before inserting them shallowly and vertically into the compost.
Covering the compost with a thin layer of sharp sand prior to inserting the cutting also helps prevent rotting.
(The sand will trickle into the hole to form a drainage layer)
It can take 1-2 months for roots to appear.
When they do appear, gradually reduce the temperature and humidity in the heated propagator / plastic bag.
As soon as plants are large enough to handle, pot into 75mm (3”) pots of potting compost.