If you have fallen in love with cacti and would love to get one or even start a collection, you might be interested in learning about them first. Cacti (or cactuses) are cute plants and are quite hardy. But before you dive in the world of cacti, let’s learn more facts about them. In this post, you will learn about cacti habitat, learn differences between cacti and succulents, and find out about their light, water and other needs.
What are cacti? Are cacti succulents?
All cacti belong to the group of plants called succulents. Succulent plants store water in their leaves and can survive periods of hot weather and drought. Cacti also don’t like humidity and prefer good airflow. There is a big myth that all succulents are cacti. Remember this phrase and it will be easy to remember. All cacti are succulents, but not all succulents are cacti. For example, a popular Aloe Vera is a succulent, but not a cactus.
All cacti = succulents, but not all succulents = cacti.
What is the difference between cacti and succulents?
- Only cacti have areoles. Areoles are soft and fluffy-looking cushiony areas from which the spines, flowers, fruits and hairs grow. While some succulents might have spines, they are not cacti because they
lack these areoles. All cacti develop areoles very early, from around 2-3 weeks. Areoles are organs, same as buds on trees. - Most succulents have leaves, but most cacti don’t have any leaves. Their spines are adapted leaves that help them lose less water in deserts and other hot habitats.
- Cacti flowers are unique from other succulent flowers. Distinguishing the flowers can help identify cacti.
- Almost all cacti are native to America (mainly USA and South America). Before the cacti trade began, they were only naturally found in America.
- Cacti’s spines are independent organs. If you try to break a spine on a cacti, it should be easy to do so. A spine will also come off without damaging plant’s skin. In some other types of plants, spines grow from epidermis and if you try to break them, it will also break the skin. An example of a plant with spines growing from the epidermal layer are Euphorbia, or Spurge.
Where do cacti grow?
The main habitat for cacti are USA and most parts of South America. In South America, cacti can be found in Mexico, Argentina, Bolivia, Peru and other countries. But there is also one species of cacti that is found in Africa – this is the mistletoe cactus, or Rhipsalis baccifera! Mistletoe cactus is native to America, South Africa and even Sri Lanka.
How many types of cacti are there?
There are around 2,000 species of cacti. Most of them are in a genus of Opuntia and cactoids, or Cactoideae. There are also Pereskia and Maihuenia species of cacti that are less common. They look less like cacti, and have leaves, and even stems that are covered in bark!
Do cacti need water at all?
Of course, cacti need water to survive! While cacti have spines (adapted leaves) that help them lose less water in hot habitats, they still need water to live. Cacti need water to grow and produce flowers, and they usually rely on rainfalls in the wild for watering. Watering frequency will depend on a type of cactus and time of the year. Cacti also need some watering in winter.
Do cacti need light?
Most cacti prefer bright and direct light. But as always, there are exceptions. One of the cacti that doesn’t need bright light and prefers more shade is a Christmas cactus, or Schlumbergera. Some cacti prefer bright, but indirect light.
Do all cacti need same care?
No, all cacti are very different and need specialized care. This is why it is very important to know that cacti classification helps to know which cactus you are dealing with and what care it needs. Classification and knowing the types of cacti is important for hobbyists that would love to start collecting cacti.
Do cacti produce edible fruits?
Some cacti species produce fruits that are edible and are even fed to animals (often cattle). Some of the most popular fruits that cacti produce are ones by genus Opuntia, or commonly known as Prickly Pear. One of the other popular fruits produced by cacti are Dragon fruits, produced by Hylocereus undatus, or white-fleshed pitahaya. Pitathya also means a dragon fruit.
This is a popular dragon fruit produced by cactus Hylocereus undatus
Are cacti poisonous?
No, cacti plants are not poisonous. Some cacti genera even produce edible fruits. The main damage you can do to yourself with cacti is prickling yourself. While most cacti have spines that can prickle, some have spines that can seriously irritate your skin.
For example, Opuntia cacti not only have spines, but also thin needle-like spines called glochids. These glochids, or glochidia, are very thin and also barbed – once in the skin they cause pain, irritation and can be hard to take out. This is because they are thin and easily break from the plant and in the skin.
Many cacti are prickly and need to be handled carefully
Are cacti hardy?
Cacti are quite hardy, but they are not indestructible. Almost all cacti require bright direct light to grow and flower. You must also not overwater them and use suitable soil. But each cactus needs specialized care, so you must follow the rules for keeping it alive. Most will also need a rest period in winter.
Do cacti flower?
Yes, all cacti flower, but when this happens will depend on environmental conditions and cacti’s genetics. Cacti flower during warm seasons of the year, such as spring and summer. Your cactus has to reach maturity to flower.
All cacti are different, and some will flower earlier than others. Most cacti will skip flowering if there is no enough sunlight. After your cacti has flowered, it will flower again each year if the conditions are optimal.
How do cacti preserve water? Cacti adaptation to live in deserts.
First of all, cacti have adapted leaves – spines. Spines have much smaller surface areas than leaves, which reduces amount of lost water. What is more, cacti have long thin roots that quickly absorb water in case of a rainfall. Cacti stems can also open up or contract depending on weather and how hot it is.
With a rainfall, stems expand to absorb more water and store it for hot times. And more, transpiration (water evaporation from the plant’s surface) in cacti doesn’t happen during the day. Instead, they do it at night to minimize water loss. Cacti spines is also a form of adaption to living in deserts – prickly spines protect cacti from being eaten.
How do cacti photosynthesize?
Cacti have fleshy stems that help them photosynthesize effectively. But unlike most other plants, cacti preserve water when photosynthesizing. Photosynthesis starts by taking in carbon dioxide, which is also coupled with loss of water. Cacti have adapted by photosynthesizing at night and closing stomata (pores on the leaves) during the day to minimize water loss.
Do cacti grow slowly? And how long do cacti live for?
Most cacti have a short period of growth. But this doesn’t mean that all cacti are slow growers. But, you need to consider that they live for many years. Most cacti kept indoors live for 15 years or more, but in the natural habitat they can live for 100 years or more!
Do cacti need feeding?
Yes, you need to feed cacti with high-potash fertilizers. The best practice with feeding cacti is to fertilize them 1 time in spring (around April), second time in mid-summer (around June), and one time in the beginning of autumn (around September).
Do cacti have genders?
Most cacti are propagated by stem or leaf cuttings or by dividing offsets and planting them. But to get seeds from a cactus, it will need to have a flower. Most cacti will require cross-pollination (being pollinated by another cactus). But some cacti will not need cross-pollination.
Cacti flower will have both ‘male’ and ‘female’ parts to it – a stamen and pistil.
To get seeds from a cacti, you will need to shake the pollen from the stamen to the pistil’s stigma. So generally, cacti are both male and female. Cross-pollination can be done by insects or by hand, using a brush to transfer pollen dust from male to female parts. This is also how cacti reproduce.