By Harry Lewis of Living Desert Plants
Many succulents are quite easy to propagate, and usually only require that one pulls off a leaf or two in order to grow more plants. Not so, however, with the genus Haworthia.
Haworthia, a genus that is indigenous to southern Africa, has become popular collectors’ items, with species such as Haworthia truncata (commonly known as “perdetande” or “horse’s teeth”) being absolute must-haves for enthusiasts. Hybrid plants and odd mutations, such as variegation, have only recently caught the attention of the general public. With many exceptionally rare and beautiful plants slowly becoming more available in the collecting community, many people will be interested in learning how to propagate their best specimens.
The most important thing one has to keep in mind when propagating Haworthia is that they cannot grow from pure leaf tissue. Haworthia leaves contain no meristematic tissues, or growth cells. The stem is the only plant part that contains this tissue, and this is what allows regrowth. Therefore, any Haworthia propagations must have at least some meristematic tissue from the stem.
Keeping this in mind, there are three main techniques that can be used to propagate Haworthia. These are leaf cuttings, root cuttings, and coring. I only opportunistically take leaf cuttings, as I believe it to be an overly complicated technique with a higher risk of failure. Root cuttings are far easier and less invasive, whereas coring is much faster to produce pups.
For effective propagation, all of these techniques require that the plants be removed from their pots. I also suggest giving the plant a gentle rinse to clean off any particulates and lower the chance of infections. You will need a sharp, sterile scalpel, some clean fishing line, and a flat surface to work with.
Leaf cuttings on Haworthia are a reasonably steep learning curve. This method generally only works with Haworthia that have thicker leaves. Plants such as H. truncata work well, whereas H. arachnoidea would be incredibly difficult. Remove any roots that are growing close to the leaves so you have ample space to work with. Make incisions on the stem on both sides of the leaf, and along the base of the leaf. Carefully pull on the loosened leaf. Make sure that it comes loose with some of the stem tissue on its base. After removing the leaf from the plant, let it dry for 3-4 days. It can then be placed on top of the soil, with some soil covering the base. A mix with fine Ibaraki Akadama or crushed 2 - 4mm LECA is a good choice for soil in this case, as these provide stability to the leaf. Water lightly after 2 weeks and roots should start to form. Pups appear after 2-3 months.
Figure 1: Leaf cutting of Haworthia truncata in a mix containing crushed 2 - 4mm LECA
Root cuttings generally only work on Haworthia with thick, tuberous roots, such as H. truncata and H. maughanii. Use your scalpel to make a small circular incision in the stem around the head of the root. This will loosen the root enough for you to safely remove it. Make sure that a piece of the stem comes off with the root, otherwise the root is likely to shrivel up. You can plant the root so that about 5mm sticks out above the soil. I suggest using the same soil mix used for the adult plant, so that the roots don’t experience as much transplanting shock. In this case, I use pure Akadama for my root cuttings. Pups should appear in 2-3 months, and in my experience should be large enough to safely plant on their own after about 18 months.
Figure 2: Root cuttings of Haworthia truncata planted in Akadama
Coring is, in my opinion, the single most effective technique to multiply Haworthia. It is, however, also the most nerve-wracking, as it is essentially cutting your plant in half! If done correctly and at the right time, plants will start to produce pups in less than a month, and they should be removable after 12 months. It is best done at the start of the growing season (which varies for each species), as this is when the plant is normally expending the most energy into producing new leaves. With coring, this energy goes into producing pups instead.
The easiest way to core a plant is to use fishing line. Gently work the line through the outermost or lowest ring of leaves on the plant, as close to the base as possible. You can gently pull leaves apart to allow the line to slide lower. Both ends of the line should meet once it is completely worked in, and should be facing towards you. Firmly pull each end separately until you start to feel resistance, which will mean the line has started cutting the stem. Once this is done, pull both ends over each other so that the line forms a complete circle around the stem. Then, pull both ends in opposite directions until it cuts completely through the stem.
Figure 3: Coring a Haworthiopsis attenuata using fishing line
It is important to keep some leaves on the base, otherwise the core will not be able to produce energy to survive and create pups. You should immediately replant the base of the plant, as you do not want it to lose roots to dehydration. Make sure as little soil particles as possible end up on the cut section to lower the chances of an infection. You can use tweezers to remove any large particles. Let the “head”, or top part of the plant that you cut off, dry for 3-4 days before replanting. It is incredibly important that the head does not receive any water at least for the next month. During this time period, the cut section is highly susceptible to mold and fungus if it gets water.
After replanting the head, I suggest using a piece of aluminum wire to secure the plant in the soil. This wire is often used to curate bonsai trees, and is a safe method for succulents as well. Haworthia roots grow rapidly and have surprising strength in them, and tend to lift unsecured plants completely out of the soil! This is especially true in my gritty mixture, which consists of 2/3 fine Ibaraki Akadama and 1/3 crushed 2 - 4mm LECA. While this mixture provides space for the roots to breathe, it also gives them something to push against!
Figure 4: Haworthia atrofusca “Mutant”, head and core, planted in my gritty Akadama/LECA mix
Figure 5: Replanted head of Haworthia atrofusca “Mutant”, planted in my gritty Akadama/LECA mix
Figure 6: Successful core of Haworthia truncata, with pups forming after 1 month, planted in pure Akadama
Harry Lewis is a qualified nature conservationist, with a National Diploma in Nature Conservation from Cape Peninsula University of Technology, and an Advanced Diploma in the same field from the University of South Africa. Between 2015 and 2018, Harry worked with large carnivores, such as lions and leopards, but has now moved back to his hometown of Stellenbosch. He has always had a passion for everything nature, including succulents, and now runs Living Desert Plants, a small succulent nursery, from his home. He specializes in growing Haworthia, but also stocks a wide variety of mostly indigenous succulents.
To contact Harry Lewis you can call him on 0741951144, email harryLivingDesert(at)gmail.com and follow him here: www.facebook.com/LivingDesertPlants/