Cacti vs Succulents…….whats the difference?
Did you know that all cacti are succulents, but not all succulents are cacti? Cacti are a more select family group ‘Cactaceae’ with specific characteristics that distinguish them from other succulent varieties.
Cacti have dense waxy fleshed stems that store water, and shallow root systems. Most cacti don’t have leaves or branches, which contribute to their ability to withstand harsh, drought prone environments. The outer skin on a cactus is usually thicker than that on other succulents. In comparison, succulents store water in their leaves, roots and stems.
The key difference that distinguishes a cactus from other succulents are areole. The small white, fluffy-like bumps, which are often the growth points for spines, hair and flowers. Non-cacti succulents do not have areole.
The spikes and hairs on cactus have two main functions…….to protect the plant from predators, and to capture moisture from the air to help it drip down into the shallow root system.
History
The word Cactus is derived from the Greek word kaktos meaning spiky. The word succulent is derived from the Latin word sucus, meaning juice.
Cacti are native to the Americas. Succulents are said to originate from a much wider area including the African and European continents. There are no species native to Australia, and many varieties are actually considered an invasive pest species, for example, the prickly pear.
Cacti and succulents are now found around the world in a wide variety of environments ranging from harsh dry deserts, to lush tropical rain forests and mountains. This part of the reason that a one-size-fits all care regime doesn’t apply to all varieties.
How to Grow
There are generally three ways to grow cacti and succulents…… from seed, from stem cuttings or from offsets which are commonly called ‘pups’.
Growing from seed
While this is a very rewarding method of growing, it is the slowest way of growing new cacti and succulents. The key is definitely having patience, and lots of it. Some varieties can take many years to develop into a desirable size. Here at the Potted Patch we are germinating and slowly growing babies from seed year round, even in the cold of winter with the help of some efficient heat mats and LED grow lights.
Seed germination can take anywhere from several weeks to many months, even in the best controlled environments.
Germination methods and success rates will vary significantly depending on the variety being grown, climate and conditions.
There is a lot of information available online to provide guidance on various soil mixtures, conditions and methods of seed propagation for all varieties of cacti and succulents.
Seedlings are ready to be transplanted into small pots when they are approximately the size of a marble, which generally takes between 6-12 months. From here, we keep seedlings in the greenhouse for two or more years until they are ready for bigger pots and moving on to their new forever homes.
It is also important to remember that seeds do not always grow true to the parent plant. If you are wanting an identical offspring, then best to propagate via cuttings or offsets.
Growing from leaf or stem cuttings
Succulents are incredible easy to propagate from leaves. This is best done in the warner months of spring and summary, but can be done year-round with the use of a heat mat and grow lights. This is a very brief summary of this method of propagation, there are countless numbers of articles and online instructional videos to learn what you need to do for your variety of succulent, and in your climate.
Carefully twist firm healthy leaves off your parent plant (don’t use leaves that are damaged or looking unhealthy) and leave them in a shaded spot out of the sun (or indoors) to callous. Depending on your climate this will generally take a few days up to a week.
The next step, can be done a few different ways. Many people lay their calloused leaves on top of dry sand or potting soil, others leave them laying on a plate.
We place ours on slightly damp, sterilised potting soil containing a mix of 50% perlite, with the callous angled slightly towards the surface of the mix.
We use a potting mix designed specifically for succulents as it is very coarse with high drainage levels.
All methods work well, the most important thing at this stage is ensuring they do not receive any direct sunlight. Indirect sun only, either via a protected window ledge indoors, or outside in a fully shaded area, or greenhouse with indirect light or shadecloth. Mist slightly if the mix is becoming too dry, but not so much that it becomes wet.
The roots with start to grow and stretch as they seek out water, usually within approximately 2-3 weeks. At this stage the cutting cat be left to continue, or angled more to encourage root growth into the potting medium.
Most will then start to develop their pups within a few more weeks, which is a very rewarding process to watch.
The parent leaf will start to shrivel and die as this is where the pup is initially obtaining all of it’s nutrients. Once the parent leaf falls off the cutting then needs careful light watering until ready to repot.
Gradually harden off your cutting if moving it into more natural conditions. Most of our cuttings remain in the greenhouse for up to 2-3 years, depending on the variety.
Stem cutting is very similar, using only healthy looking stems and wait a few days for the cut tip to callous over. We remove enough leaves to have a few centimeters of stem that is dipped into cutting power.
This is then planted into a succulent potting mix in seeding plugs.
Plant the stem right up to the first set of leaves to help promote a deep, healthy root system.
Do not overwater or your stem and any small roots may rot. Wait for a healthy root system to emerge from the bottom of the seedling plug, then carefully repot. Just like leaf cuttings, be sure to avoid direct sun during this growing phase.
Growing from offsets/pups
This is the easiest and quickest method of propagation. Not all varieties of cacti and succulents grow pups. For those that do, pups may grow from the base of the parent plant, from stems or pads.
Pups are removed wither by gently twisting, or by using a sterilized very sharp blade to made a clean cut.
A clean cut is essential to ensuring the wound on both the parent plant and the pup can dry and callous without nasties causing infection.
For larger cut areas, we use a dusting of sulphur powder for added protection.
Depending on the variety and size of the plant and pup, callousing can take anywhere from days or weeks….to months.
Once calloused, the pups can be potted up. With some care & patience, these cuttings will develop into lovely new plants with the same characteristics of the parent plant. Be sure to do some homework about the variety you are growing to best increase your chance of success. Soil types, watering regimes, fertilising, heat and light requirements can vary significantly.
Care & Maintenance
This is the part where a little research will definitely pay off. With thousands of varieties of succulents available, it won’t be a surprise that the care regime for some varieties can be very different to others. Take a little time to identify your plants and the different needs they may have. This will help ensure you give them the best love and care for them to stay happy and healthy.
Light & Temperature
Cacti generally need l lot more sunlight and warmth than other succulents. Approximately 10-14 hours of direct sunlight is needed, depending upon the temperature and strength of the sunlight in your region. The area in which they are planted will also impact the plants warmth and exposure, for example planted in an open garden bed vs in a pot up against a hot brick wall. Most cacti are very hardy, but always keep an eye on them in scorching summer sun to ensure they are not getting sun damaged. Similarly in winter…. closely monitor your cacti over colder months, particularly if you have heavy frosts or snow where some additional protection might be needed.
Non-cacti succulents are more susceptible to sunburn than cacti. While they enjoy some direct sun, be careful in direct hot summer sun. Filtered, indirect light is best during these harsh periods. A shade house or simply some shade under the edge of a patio or on a protected windowsill is perfect. If using a greenhouse, it is critical to ensure sufficient airflow, as extended humidity can lead to fungal infections that can damage or even kill your plant. If your indoor plants are suffering from excess humidity, a dehumidifier in the room can assist in balancing the air quality.
Growing your cacti and succulents in pots is a great way to provide them extra protection for the extremes, simply move them in or out of shade or extra cover when needed.
There is a huge range of decorative and functional indoor and outdoor plants stand available online, many on wheels that are super easy to move around.
Some varieties will happily grow indoors, other need to be outdoors.
Fertiliser
Applying fertiliser is not essential for succulents, however, many will thrive from a gentle feed early in spring as they are coming into their main growth period. Succulents are not heavy feeders, so applying a fertiliser low in nitrogen once per year should be sufficient. Most nurseries and garden supplies centres sell succulent-specific fertilisers.
If you are re-potting your plants into fresh cacti-specific potting mix, many of of these mixes have fertiliser already mixed in so this should give your plant all the nutrients it needs until next spring.
It is helpful to be aware that succulent dormancy is more complex than simply winter or summer dormancy periods. A range of varieties are winter dormant, doing most of their growing during spring and summer, and other varieties that are summer dormant, doing most of their growing through autumn and winter. Dormancy periods are also influenced by temperatures and growing conditions, so getting to know your individual plants is important. Indoor plants have less specific dormancy periods than outdoor grown succulents.
Water
This is always the area of care that has succulent lovers in fear! It is also the the area of care that varies the most depending on a wide range of factors including
- Season / growth period
- Temperature and sunlight
- Humidity and moisture
- Soil structure and drainage
- Container type and size
- Variety of succulent
- Indoor vs outdoor growing
Some plants need more frequent watering than others. A general rule of thumb is that soil is better to be too dry, than too wet. Wet soil is likely to promote fungal infection and root rot which can lead to the death of your plant if left for too long.
Many beginners can be confused by the signs our plants give us about water. The symptoms of underwater can be easily mistaken for those for overwatering. Underwatered succulents are likely to have wrinkled leaves. They might be looking dry and crispy. There is an easy fix for this……..give your plant a good drink and watch how fast it recovers.
The sign of an overwatered plant are discoloured or translucent leaves which turn soft or squishy and may be falling off the plant. An overwatered cactus might start feeling soft, or you might start seeing a brown and softening base of the stem. On one occasion many years ago, I had a ball cactus that was overwatered and when I gently prodded the top of the ball my finger went straight through into a ball of rotted brown jelly! There was no recovery for this one unfortunately. On most occasions, however, an overwatered succulent can be easily corrected. Depending on the condition of the plant, it might just need some extra time to dry out. If it has been wet for a long time, or your soil isn’t draining sufficiently, the best thing you can do is to repot it into fresh succulent potting mix. This will also allow you to inspect the base and roots of the plant to check for any rot.
But do not fear! The best way to water is by infrequent soaking……think of succulents in the desert. They go through long period of dry spells then have a flood of fresh rain for hydration. Our home environments don’t need to be this harsh, but you get the picture. Do some research online for your varieties.
There are a range of growers that will advise there is a specific way you should water, but for me, it’s about getting to know your plants in your own climate. Avoid overhead watering on the leaves, either soak at soil level and allow to drain through your pot until it stops dripping, or water from below using a water bath method.
Allow soil to dry before watering again. If growing in pots, poke your finger (or a commercial water testing meter) at least an inch below soil level. If dry, water. If damp, leave it be. Plants in the ground will be different depending on your soil type and drainage. Monitor how your plant responds. It won’t take long for you to get to know what your little babies like.
It might seem obvious, but succulents need more frequent watering during warmer months. Not only because of the warmer weather, but also because this is the period that most succulents are going through their growth phase for the year. There is no magic number for the frequency of watering simply because conditions can vary so widely. Watering can range from once or twice a week in the heat of summer, to once once or twice over the while winter period.