People often say, “You can never kill a cactus plant,” and that is true if the cultivation conditions are right. I have known people who had killed heaps of cactus plants despite all the tender loving care they gave looking after those plants. That also includes myself, even though I have successfully nurtured hundreds of cacti all my life by just knowing how to propagate Cactus. Sometimes, plants just succumb or give up when only one condition does not suit them.
Cacti are popular plants that are grown in many countries. There are many collectors of cacti all over the world. These hardy plants can be grown indoors, outdoors, in greenhouses, and under glass. They are relatively easy to grow when conditions are right.
Also, Read How To Care For Cactus Plants
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Cactus Propagation Methods
Propagation is the process of producing new plants from the plants you already have. In the wild, propagation from seeds is the most common method. This is achieved from flowering, pollination, fertilization, and eventually seed formation. As natural habitats of succulents and cacti decline, the need to propagate and maintain these species in cultivation becomes more and more crucial for their survival.
Not only that, but propagation has become part of the charm of growing these plants. Growers and hobbyists who have tried their hand at propagating succulents find it highly rewarding and engaging.
There are several ways to propagate cactus plants, which includes;
Propagating Cactus by Seeds
Cactus seeds are available from many specialist suppliers. Most cacti species can be propagated from seeds. This process is slow and requires a lot of time and patience but can also be highly rewarding when successful. Cacti with solitary growth habits are usually propagated by seeds. Seeds can be harvested from the plant’s flowers. The flowers need to be pollinated either by pollinators or through self-pollination.
Self-pollination can be achieved by using a paintbrush to pollinate the flowers. If all goes well fertilization will occur. The flowers can then be dried and stored and seeds harvested from them. The harvested seeds need to be provided with the right environment to germinate into seedlings. To germinate cactus seeds, sow the seeds thinly on the surface of the cacti compost and then cover the seeds with a thin layer of grit.
Remember to label the containers if you are growing different varieties of cacti. The optimum temperature for seed germination is around 21°C. It is necessary to maintain a fairly humid atmosphere for the seeds to germinate. The best way is to cover the pots with plastic bags or sheets of glass. Once germinated, the seedlings can be exposed to more light and air but they have to be kept moist at all times.
Propagating Cactus From Offsets/Offshoots
Many cacti species propagate asexually by means of growing lateral shoots or offsets. Not all cacti produce offshoots. The ones that do include echinopsis species, mammillaria species and many others. Offshoots can be carefully removed and placed in a suitable potting mix to start a new plant. Removing offshoots from the mother plant helps to refocus the energy to the growth of the main plant.
Propagating Cactus by Cuttings
Cacti propagate readily by cuttings. This method is easier than the above when propagating cacti plants. Use a sharp knife to cut a piece of the cactus for propagating. It is important to keep the cut surface of the cutting clean. The cutting also needs to be left in the shade for three to four days to allow a dry callous to form over the cut area. Once the callous has formed the cutting can be planted into moist well-drained soil.
Rooting powder is not really necessary for propagating cuttings but it may be helpful. It may take several weeks or months before the roots appear. Do not water the newly planted cuttings until they start to form roots. Some cacti that commonly propagate from stem cuttings are Opuntia or prickly pears, Columnar cacti, Pincushion and Globular cacti and Cacti cuttings for propagation.
Propagating Cactus by Grafting
Another way of propagating cacti is by grafting. This method is usually used on cacti species that are difficult to propagate or weak growing species. Grafting is the process of taking a cut piece of cactus and attaching it onto a severed piece of another cactus. The cut or grafted part is called a ‘scion’ and the base or rooted part is called the ‘rootstock’.
Grafting requires a compatible and hardy rootstock. Compatibility is very important for grafting to be successful. The compatibility is higher when the rootstock and scion are from the same species. The compatibility decreases the further the cacti are in their genetic relations. A vigorous rootstock is required for this grafting method.
The cutting is placed on top of the rootstock and then secured with rubber bands. This grafted plant is then left in a warm place out of direct sunlight for several weeks. The rootstock helps to provide nutrients to the cutting that is attached on top and keeps it alive.
Cacti grow well on a sunny window sill and will flower when the temperature and soil conditions are right.
Also, Read How to Grow Succulents From Cuttings
How to Root a Broken Piece of Cactus/ Propagate Cactus
Disinfect your knife. Use a sharp knife that has been cleaned or disinfected. You can do this by washing with warm soapy water or wiping with rubbing alcohol. Be careful to disinfect every time you perform a cutting by wiping the knife with alcohol to avoid introducing fungus or diseases.
Inspect the broken end of the cactus. If you find uneven or jagged cuts from where it broke off, cut out the uneven edges with a sharp clean knife to even it out.
Let it dry. Set the broken piece aside and let it dry and callous over to heal. This may take anywhere from a couple of days to weeks depending on the size of the cactus and the humidity. Keep the cut in a bright location but away from direct sunlight.
Prepare the pot. Choose a pot with drainage holes that is appropriate for the size of the broken cactus. Fill the pot with a suitable cactus mix that is well draining.
Dip in rooting hormone (optional). You can dip the dried end in rooting hormone before planting. This step is optional.
Plant the broken piece. Put the dried end into the potting mix about ⅓ into the soil. Make sure the piece is standing erect. Pack the soil around the plant to secure it. Place the pot in a bright location but away from direct sunlight.
Wait before watering. Do not water until two to four weeks later. Then wait until the soil is completely dry or two weeks later before watering again.
Increase sunlight. The roots will start to form in about two to six weeks. You can check for roots by pulling the plant. If you feel resistance while tugging, the plant has started developing roots. Once roots are more established, you can slowly increase the intensity of sunlight it receives.
When Not to Propagate a Cactus Plant
Cacti, just like succulents, are among the some of the easiest plants to root and propagate even for beginners, which adds to their appeal. Cacti can be propagated any time of the year, but cactus cuttings root fastest around the summer months to early autumn. To ensure propagation success, try not to propagate during these times:
During a Heatwave
It is not the best time to propagate during a heatwave. When plants are stressed and focused on survival, they are not in the best condition to multiply. It is better to wait until the heatwave has passed or during a milder, less hostile season to get the optimal result you are looking for when propagating.
Pruning and cutting your plant for propagation also introduce more stress to the plant, as it needs to focus on healing and regrowing as well as surviving these harsh conditions. However, if plants are kept indoors and protected from the intense heat outside, or kept in a temperature controlled environment, then propagating during a heatwave doesn’t pose that much of a problem.
During Frost or Freezing Temperatures
Cacti go dormant during freezing temperatures and frost. During frost, plants shut down and are not actively growing. Propagating your plants around this time is will not provide the best results you are aiming for. Wait until frost is over before you propagate to ensure the optimal survival of the plants.
Propagating around this time makes your plant more susceptible to diseases and rot. Pruning or cutting your plant for propagation during this time introduces new stress to the plant as it needs to focus its energy on healing and regrowing.
Basic Cactus Care Tips
Below are some quick and easy tips on how to look after a cactus plant. Follow the guidelines and you will be rewarded with blooming flowers from your cacti collection every year.
- Use a good quality cactus/succulent potting mix.
- Water the plant thoroughly when it is watering time.
- Do not overwater or allow the plant to stand in water.
- Have sufficient sunlight for your plant.
- Place your plant in a well-ventilated area.
- Let the soil dry up before the next watering.
- Feed with mild liquid fertiliser during the growing season.
- Minimal or avoid watering when the plant is dormant in winter.
- Pot up every 2-3 years depending on growth.