The first thing to realize is that the words "cacti" and "succulent" are general terms. Cacti belong to a specific family of plants, but the species within that family come from some very different habitats. Many cacti, such as those in the genus Ferocactus, are in fact true desert dwellers. Others, such as those in the genus Echinopsis, live in the grasslands of South America, those in the genus Oreocereus live in the high Andes mountains, and those in the genus Epiphyllum live in jungles and don't even live in the ground, but upon other plants.
When talking about succulents, it gets even crazier. The term "succulent" is completely non-scientific, and basically can refer to any plant with fleshy parts (leaves, stems, or roots), usually which are adapted for storing moisture in times of drought. These plants come from all over the world and live in all different habitats.
Why do you need to know all of this? Well, the more you know about your "Assorted Succulent" or "African Zipper Plant," the more chance you have of being successful growing it. If you are lucky enough to live in an area that has a local cactus and succulent club, visit one of their meetings, bring your plant, and be prepared to find out all kinds of things about it, like what its real name is, where plants of its type grow in the wild, and what growing conditions it likes.
If you aren't so lucky to have a local cactus and succulent club close by, or are just too eager to get started caring for your new baby, all is not lost. There are some general rules that can be applied to those plants we call cacti and other succulents. Read on....
Watering and FertilizingMany people think that cacti and succulents require a small amount of water every once in a while. While its true that these plants are tough, and can usually survive under such circumstances, most certainly will not thrive.
During their growing season, these plants like regular watering and fertilizing. For most, the period of growth is from Spring into Fall. Many plants rest (stop putting on growth) from late Fall to early Spring, when temperatures are cool and daylight length is short, and during mid-Summer, when temperatures are at their peak.
How often to water and fertilize: While growing, cacti and succulents should be watered at least once a week. Some people water more often than this. During each watering, give the soil a good soaking, so that water runs out of the 'drainage holes' of the pots. During the growing season, a balanced fertilizer, which has been diluted to 1/4 strength, can be added to the water for each watering. (A balanced fertilizer is one that has roughly equal proportions of Nitrogen, Phosphorous, and Potassium. A 10-10-10 fertilizer diluted to 1/4 strength is ideal.)
When the weather cools and day-length shortens, plants enter a rest period. During that time, increase the interval between watering, and let the potting mixture dry out between watering. Some people say that during dormancy, cacti and succulents should be given just enough water so that they show no sign of shriveling. Use some common sense here. If your plants are kept indoors on a window sill in a heated room during the Winter, they will need more water than if they were over-wintered out-of-doors. In any case, do not fertilize your plants during dormancy.
There are exceptions to the above guidelines, as some cacti and, especially some succulents, are Winter growers. Again, your local cacti and succulent club can help you determine the particular growing habits of your plants.
A word about water: Tap water often can be alkaline and/or hard, meaning it contains high concentrations of dissolved minerals. Such minerals can build up in the plant's 'soil' over time, causing harm. This is one good reason why your plants should periodically be 'repotted.' Buildup of such minerals can also cause unsightly deposits to form, especially on unglazed clay pots. Never water your plants with water that has been through a softening system that uses salt as a recharging agent, as these systems simply replace the "hardness" in the water with sodium ions.
Rain water is preferable to tap water, if you can manage to collect and store it.
LightMost cacti and succulents like bright light, but not all can tolerate intense, direct sunlight, especially in conjunction with high temperatures. The intensity of the light that a plant will thrive in depends on the species. A plant that is grown in optimal light conditions will "look normal" (unstressed), and is more likely to flower than one grown in sub-optimal lighting conditions. (Keep in mind that succulents, and especially cacti, have very differing ages at which they will flower. For example, even if you give your Giant Saguaro seedling (Carnegia gigantia) conditions that are optimal in every way, you will likely not see it flower in your lifetime.)
While optimal lighting conditions depend on species, there are some general signs that indicate your plant is getting either too much or too little light:
Too much light: When your plant is getting too much light, it can appear "off color," taking on a "bleached out" look, or turning yellow or even orangish. Keep in mind that these signs can also indicate other stresses, such as disease or too much water, so use common sense when making your diagnosis.
If your plant is moved suddenly into very bright sunlight conditions, or if the weather suddenly turns hot with abundant sunshine, your plant can scorch. This can happen very rapidly and can scar the plant for the rest of its life, so be on alert for when such a condition might occur, and take precautions to prevent scorching.
Too little light: If your plant is receiving too little light, it might etiolate and/or appear to really reach for the light source. (Etiolation is the condition where a plant becomes "drawn," for example, a cactus plant that is normally round begins to look as if it is being stretched out from the growing point at its center). Your plant will suffer if left in such light conditions for very long. When transitioning such a plant to stronger light, keep in mind that it will be especially prone to scorching, so make the transition slowly.
Note that in most cases, it is quite normal for a plant to slowly grow toward the light. What you want to avoid is the condition where it is really reaching for the light. For example, if your columnar cactus is bent toward the window at 90°, it's trying to tell you something.
For a potted plant that slowly grows toward the light over time, you can rotate its pot to cause it to grow in a more balanced fashion. Remember, if you do this, that the side of the plant that had not been exposed to direct sunlight for a long time might scorch if you make the transition too quickly. Be careful!
Pots and PottingPots come in all kinds of styles, and are made of various materials.
Pot materials: The materials used most often for pots are plastic and clay/ceramic (either glazed or unglazed). Cacti and succulents can be grown successfully in pots made of either material, and choosing one over the other is usually a matter of personal preference.
Plastic pots are lighter, usually cheaper, take up less room compared to clay or ceramic pot with the same inside dimensions, and are easy to keep clean. Plants kept in plastic pots also tend to require less watering compared, especially, to those kept in unglazed clay pots.
The extra weight of clay and ceramic pots provide stability for tall or top-heavy plants. Many people also feel that a good clay or ceramic pot just plain looks better than a plastic pot. Remember that if you water with hard water, a buildup of minerals on the outside of unglazed clay pots can cause unsightly deposits to form.
Regardless of the material the pot is made of, it must allow good drainage. It is very difficult, if not impossible, to grow a cactus or succulent successfully in a pot that lacks drainage holes. If you find a pot that is perfect in every respect except for its lack of drainage holes, drill them yourself.
Styles of pots: If you know the species of cactus or other succulent you have, you can make a better choice as to what style of pot to keep it in. For example, many species of cacti have fibrous roots that remain close to the surface of the soil. Such a plant has no use for a narrow, deep pot; a shallow pot with a relatively large diameter would suit it much better. Many cacti and succulents, while appearing quite modest above the soil line, have a massive, deep, tuberous root system below the soil, and require a pot suited to that root system.
Some people like to use bonsai pots for their plants. These pots are often very attractive, and a specimen planted and skillfully staged in such a pot can be a real attention-grabber. If you have limited space, be aware that bonsai pots tend to take up a relatively large amount of space, and their price can be a real attention-grabber also.
Soil: Cactus and succulent potting mixes are sometimes available commercially, but many people like to create their own special mix for their plants. There are some basic characteristics that a potting mix for cacti and succulents should possess. Perhaps the most important characteristic is that the soil should drain very well. The best way to achieve this is by adding horticultural-grade sand and grit to the compost component of the soil. Many believe that a good starting ratio for the mix's components are one-third compost, one-third horticultural-grade sand, and one-third grit.
For the compost component, a growing number of hobbyists believe that a peat-based compost should not be used, as it seems to contribute to pest problems like 'root mealy bug' and 'fungus gnat', and doesn't contribute much in the way of nutrients to the plant. Many people start with a good grade commercial potting mix for the compost component, and some sift it through a screen to remove such "undesirables" as the small pieces of wood and twigs that can sometimes be found in such mixes.
All sand is not created equal. The sand component should be horticultural grade, relatively coarse, and sharp. Never use non-horticultural grade sand, such as fill sand, as this is usually not washed, and can contain, among other things, salt.
For the grit component, most people agree that horticultural pumice is the best. It is also not widely available, and can be expensive if you can find it. Some other materials that can be used include pearlite, porous gravel, and lava fines. People often have good luck using fired clay products for the grit component. These products include certain cat litters and products that are used to absorb oil spills. If using one of the clay products, you must ensure that it is a fired clay that does not break down and turn to mush when it gets wet. Check the labeling, and to be sure, test it out by putting some in a jar of water for some time to see if it breaks down. Mush in your potting mix will do your plants no good.
Like everything else discussed so far, there are no hard and fast rules for potting mixes, so you'll need to experiment with ratios. The above ratio of components represents a good starting point.
Repotting: Ideally, your plants should be repotted every year so that you can provide them with fresh soil, inspect and address problems with their root systems, and move them to bigger pots if necessary.
"Every year; yeah right," you're probably saying. You're not alone in saying that. For best health, however, your plants really should at least be repotted when they start telling you they're not happy in their current "digs." If your plant looks out of proportion with its pot, is pushing its way up out of the pot, has roots that are growing out through the pot's drainage holes, or is spitting the pot, guess what....
To re-pot, invert the pot and gently tap it to loosen the soil and roots from the pot. If the plant is really root-bound, you might need to resort to breaking the pot to get the plant out.
Next, clear away the old soil from the roots. Be careful when doing this, as you want to minimize damage to the roots. A thin stick, such as a chopstick, helps in this regard. Using the stick, gently tease out the roots and remove old mix. This is a good time also to inspect the mix for 'pests'. If any roots appear dead and dried out, they can be pruned off. Note that some people use a sharp stream of water, as from a hose, to wash the mix from the roots, rather than use the stick method.
Repot the plant into the new pot, which should be a little larger than the old one, and in pleasing proportion with the plant. First, cover the drainage holes with clay pot shards or screening (your pot does have drainage holes, right?), then place the plant in the pot with fairly dry, fresh mix. You might want to apply a top dressing, such as crushed granite, but this isn't necessary. Now, don't water the plant right away. Instead, allow the plant to rest out of direct sunlight for a week or two before watering it. This allows any roots that were damaged to heal, as unhealed wet roots are very susceptible to bacterial or fungal infections.
Old Wife's Tale debunked: Remember your grandmother told you to always add a layer of pebbles to the bottom of a pot when repotting, to improve drainage? Your grandma might have made the best cherry cobbler in the world, but forget this advice about pebbles. The potting mix in your pots should extend all the way down to the bottom.
A word about handling your plants: Cacti and succulents grow in some extremely hostile environments, and as such have evolved some very inventive ways of defending themselves. They will not hesitate to use those defense mechanisms when you attempt to repot or otherwise handle them.
Unless you're REALLY tough, you're probably wondering how in the world you are going to get a grip on your spiny cactus while you repot it. Some good "tools" that can be used include newspaper or paper towels that have been wadded up, or blocks of foam.
Beware that not all spines are created equal. Some can be especially nasty. For example, that group of cacti known as opuntias - commonly referred to as "prickly pears" - have spines that, at the microscopic level, are barbed and very easily break off and remain lodged in the skin. Opuntias also have fine spines called "glochids" which, in extreme cases, have gotten into people's eyes and caused problems. Some other types of cacti, as some mammillarias, have hooked spines which easily grab fast to skin and clothing.
Still, other succulents are known for having poisonous or irritating sap. Plants in the genus Euphorbia are especially known for this. Be careful around them.
Cacti and succulents are, no doubt, tough plants. They are, however, not without their problems. Aphids, snails, slugs, thrips, and nematodes are among some of the guests that can leave their mark on your collection. Below is a discussion of some of the more common pests to cacti and other succulents.
Mealy Bugs: No discussion of basic cacti and succulent care would be complete without a discussion of pests, and no discussion of pests would be complete without a discussion of our little friend, the mealybug. Mealybugs, or "mealies" as the are often referred to, are tiny insects about 0.1 inch (3mm) in length, which shroud themselves in a oval-shaped, cottony covering. It is the presence of these cottony masses, en masse, on your plants which signal the fact that you've been invaded by mealies. Mealybugs live their entire adult lives within their cottony fortresses, happily dining on plant sap. A plant infested with mealybugs will stop growing, weaken, and often eventually succumbs to rot.
Their cottony coverings protect them from predators AND contact pesticides. Minor infestations can be handled by dabbing the offending individuals with a cotton swab that has been dipped in rubbing alcohol. The alcohol dissolves the covering, leaving them defenseless. Systemic insecticides are often used to control widespread mealybug attacks.
Being ever resourceful, mealybugs can also attack the roots of your plants, in which case they are called "root mealies." If you don't see any visible pests on a plant that appears sickly, root mealies might be to blame. To eliminate, unpot the plant, and if you find any unwanted guests, wash off as much soil and critters as possible, soak the roots in a systemic insecticide, and repot.
Spider Mites: Spider mites are really, really tiny critters which are all but invisible to the unaided eye. These pests are often found in their whitish webs, which are often spun close to the plant's surface. They dine on plant sap. Infected plants often develop yellowish spots which later turn rusty brown, scarring the plant. Weakened plants are susceptible to secondary infections, be they viral, bacterial, or fungal.
Spider mites hate being wet. Of course, so do most cacti and succulents. Overhead watering and misting is often listed as a preventative and a cure for spider mite problems.
Mites are not insects, so insecticides often have little effect on them. The use of a miticide, however, is recommended for widespread problems.
Scale: Scale are pinhead-size insects that appear as raised tan or brown spots resembling marine limpet shells. The shells are actually hard coverings that protect the insects underneath. Like many other insect pests, they dine on the plant's sap. Outbreaks of scale can be treated similarly to mealybug infestations.Fungus Gnats: Fungus gnats are often a nuisance rather than a problem. When present, they are small black flies that can often be seen on and around the surface of the soil. In some cases, mostly when seedlings are involved, their larvae can cause damage and plant loss. Many hobbyists report that fungus gnats are more common in peat-based soils.