Succulents 101: Succulents vs. cacti
My posts sometimes assume a fairly advanced level of knowledge. Many of you have that, but others might feel a bit left out. To remedy that, I decided to do a series of more basic posts. Hopefully they’ll be useful for readers who are new to succulents without boring folks who are already familiar with the topic discussed.
Today’s post answers a fundamental question: What’s the difference between succulents and cacti?
Both succulents and cacti are plants capable of storing water in order to survive life in harsh, dry environments. Here are the differences in a nutshell:
Succulents
- A broad category of plants that store water in their leaves, stems, or roots. They are found all over the world.
- Includes cacti as a subset, but also agaves, aloes, echeverias, and many species of euphorbias.
- Not all succulents have spines.
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| Succulents |
Cacti
- A specific family of succulents (Cactaceae) found only in the New World.
- Distinguished by areoles (small, cushion-like growths from which spines, flowers, or new stems emerge).
- Always have spines or spine-like structures (even if small).
Therefore: All cacti are succulents, but not all succulents are cacti.
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| Cacti |
Sometimes you hear people refer to agaves and similar plants as cacti. It’s obvious what they mean, but technically, that’s not correct.
Agave: succulent ✅ cactus ❌
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| Agaves |
Cactus: succulent ✅ cactus ✅
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| Cacti |
It bears repeating: All cacti are succulents, but not all succulents are cacti.
When I was a docent at SCBG, your last statement was the mantra we used when talking to visitors touring the desert garden. They may not have understood all the nuances but they at least got that point.
ReplyDeleteMaybe people would understand the concept better if we compared it to animals: Every dog is an animal, but not every animal is a dog.
DeleteThanks for this great idea. As a relatively recent agave and Mangave addict, i have a lot to learn. In SoCal I grew orchids and ferns. Bought just one agave with me in the 16 ft truck that brought my plants. Still like ferns but agaves are SOO beautiful !!!!!
ReplyDeleteI love ferns, too. I wish dryland ferns, which share many of the same habitats as agaves and cacti, are so hard to find. I'd definitely plant more.
DeleteA friend who is in the blogging world bought me a lovely limited edition print that hangs on my dining room wall. Four succulents are drawn, one of which is an agave, the other three are cactus. Across the bottom of the print is the the print number, the female artists name, and the word Cactaceae. I wonder if anyone has ever told her of her error?
ReplyDeleteLOL. It cracks me up to know that this misconception has made it into fine art.
DeleteThe mantra is handy. However, only about a third of the evolutionarily basal cacti in the genera Leuenbergeria or Pereskia are succulent due to their tuberous roots. The rest have fibrous roots not making them succulent.
ReplyDeleteYou brought up very valid points, but they go beyond the scope of this (limited) introduction :-)
DeleteThis is a great post, and great photos and graphics to explain it. I find succulents as fascinating as all other plant categories. I have a few in pots, and have enjoyed seeing many in their native habitats during our travels. We even have some species of Opuntia cacti native here in Wisconsin: O. fragilis and O. humifusa.
ReplyDeleteIt's wild imaging cacti growing in Wisconsin - and even further north into Canada!
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