A short guide to indoor plant propagation
Propagation is the process of extending or multiplying a plant species, increasing its stock.
Indoor plant propagation
Propagation is the process of extending or multiplying a plant species, increasing its stock. There are many diverse ways in which indoor plants can be increased. Some methods such as replanting offsets are simple whilst others, such as air layering, are more challenging.
Unlike garden plants, indoor plants are not usually sown from seed. This is largely because there are more suitable propagation options, the chief of which are listed below:
Most houseplants can be raised from cuttings, which can be stem, leaf or even cane cuttings. As 100% success can never be guaranteed, it makes sense to always take several cuttings at any time.
These cuttings are taken in a similar way to many outdoor garden plants and use a non-flowering shoot. Make the cutting no longer than 15cm. The bottom end is cut just below a leaf joint, and the leaves are removed from the lower half of the cutting.
Several cuttings are inserted around the edge of a compost-filled pot and encouraged to root within a plant propagator or even inside a makeshift greenhouse atmosphere of a plastic bag.
Where leaves grow directly from the stem, cuttings are taken directly from the leaf section itself and inserted into a pot of compost to root in the usual way.
The whole leaf plus a short length of stem is taken from plants such as African violet and gloxinia, while vertical sections of a leaf can be taken from Streptocarpus and Sansevieria.
Some succulents can be propagated by pulling off a fleshy leaf, allowing the end to callus for 48 hours and pushing it into the compost.
Cane cuttings can be bought ready-to-plant, but they are an easy and satisfying way of increasing stock of thick-stemmed plants such as Dracaena and Dieffenbachia.
A mature stem carrying at least one leaf node can be cut into several pieces, and each piece laid flat onto the compost in a pot, and half-buried in the compost. The leaf joints should be pointing upwards, as these will sprout fresh growth.
This method of increasing plant stock is easy, but takes time to bear results. It is similar to layering plants outdoors, but instead of picking a long stem and pinning it to the ground in order for it to root, the long stem is pinned with a piece of wire in a hairpin shape into an adjoining small pot of multi-purpose compost.
As this method takes time, it makes sense to layer several stems at once. Signs of fresh growth indicate that the layered stems have rooted, and the stems can be cut and freed from the mother plant. This method is suitable for trailing and climbing plants such as Birds’ Foot ivies.
Some house plants conveniently produce baby plants at the end of their flowering stems or even leaves, and these can be pinned down into pots of multi-purpose compost for rooting.
Sometimes the plantlet, even more conveniently, has roots, in which case the plant can be cut from the mother plant and potted up ready to be grown on.
If the plantlet has no roots, it can be pinned into a pot of multi-purpose compost and when it has rooted, severed from the mother plant. This method is suitable for the Spider plant Chlorophytum, mother-of-thousands Saxifraga stolonifera and the piggyback plant Tolmeia.
Many indoor plants form clumps of baby plants around the main plant, and these can be repotted individually to grow on. However it is necessary to remove the whole plant from its container in order to access these clumps or rosettes of foliage.
The compost may have to be scraped away to expose the join where the baby meets the mother plant. This join should be severed either by hand or with a sharp knife. The mother plant can then be repotted and the new young plant potted up in multi-purpose compost and grown on.
This method is suitable for African violet, some ferns, the umbrella plant Cyperus and Sansevieria.
This is a clever propagation technique that creates a new houseplant without disturbing the old plant. It suits large, thick-stemmed plants such as rubber plants.
Choose a healthy stem and make a cut no more than 60cm from the tip of the stem with a leaf a few centimetres above, making sure you cut no deeper than the centre so that you have made a wound.
Push a little loose moss into the cut with the blade of the knife, pack the remaining moss around the stem and wrap a square of polythene around the stem beneath the cut, securing it with a tie. Leave for at least a growing season and then check the plant; if roots have grown through the moss, cut the stem below the layering, loosen the moss and pot up the stem.
This propagation method is suitable for a number of larger indoor plants including the Rubber plant Ficus elastica, Dracaena and, Swiss cheese plant Monstera.