Old man cactus

Old man cactus quick fact sheet

OTHER NAMESOld man cactus, Bunny cactus, White Persian cat cactus  
CLIMATEShrub-land Arid Tropical Dry
PROPAGATIONSeed propagated
HEIGHT15 meters
WATERStandard succulent watering schedule
OTHERSGrows well in spring/fall Non-toxic Prefers outdoors

What is old man cactus?

The Cephalocereus senilis is a succulent lover’s dream and a fan-favorite among the varied population of succulents.

old man cactus
Cephalocereus senilis @Amazon

Native to the arid regions of Mexico, the old man cactus is a spiky, tall, cylindrical cactus that can reach incredible heights of 10 to 15 meters or more. 

A statement succulent, the Cephalocereus senilis is unmistakable with its shaggy coat of long silver hair, which serves as the source of its nickname – old man cactus. It is reminiscent of an older man’s long unkempt hair.

Apart from giving the old man cactus its unique name and appearance, the long strands of “hair” serve another more critical, less superficial purpose – keeping the plant cool by providing shade from the sweltering sun.

These hairs are not just for decoration. They are a modified form of spines (thorns), and while they may not be sharp enough or hard enough to prick you, they hide a sinister secret.

Concealed below the layer of flowing white hairs are formidable yellow thorns (or spines), and these are sharp enough to draw blood.

Who would have guessed this harmless-looking old man succulent was capable of such trickery and defense?

The bunny cactus is a slow-growing succulent that grows well in pretty hot and arid locations. It is native to Mexico, after all, and last time we checked, Mexico isn’t known for its chilly winters.


When we say slow-growing, we mean just that. The old man cactus has lovely flowers that will take anywhere between 10 to 20 years to bloom.

However, if you’re patient enough and tend your Cephalocereus senilis for 10+ years, the succulent gods will reward you with beautiful deep red, brilliant white, or sunny yellow flowers that bloom fully at night.

Not many people get to see the Cephalocereus senilis flowers in full bloom, so count yourself blessed should you happen to be part of the lucky few.


The old man cactus is a pretty easy succulent to propagate from seeds – a fact that saved it from extinction a few decades back.

Its ease of propagation and increase in cultivation by succulent lovers supplemented the otherwise depleted Cephalocereus senilis that had been growing(dying really) in the wild.

You can gather seeds from its fruit; however, it’s simpler and faster to buy the seeds from your local gardening store or a reputable online vendor due to this succulent’s slow rate of growth.


Like most succulents, Cephalocereus senilis will do well in a quick-drain soil mix with significant aeration and drainage properties.

Check your local gardening store for pre-mixed cactus or succulent soil; the cactus mix boasts excellent porous and drainage capabilities.

If you’re more of a “hands-on” kind of guy, you can make your soil mix from home, as detailed in this article by Succulent City’s in-house botanical experts:

Learn how to DIY your planting soil at home:

How To Make Your Succulent Soil At Home

Just like any other succulent, the old man cactus isn’t too fond of over-watering. After all, it is endemic to Mexico, and last we checked, Mexico doesn’t make the news for its lush green, rain-soaked plains.

Beginners usually make the mistake of watering their succulents daily. The result is always the same – over-watering leads to the dreaded root-rot, which ends up killing the poor succulent.

Read more about root-rot in this informative article by Succulent City:

What is root-rot? How to fix it.

Just like any other succulent, wait until the soil completely dries out before watering it through and through. When you finally water the old man cactus, soak it through but do not drown the poor guy or leave it sitting in stagnant water.

Succulent cultivation 101: Succulents despise stagnant water.

Learn more about watering your succulents:

Complete Guide to Watering Succulents

Cephalocereus senilis will appreciate growing in a region with full direct sunlight, similar to its native country of Mexico.

The old man cactus is an outdoor growing succulent.

Do not leave the old man cactus outside during winter as this particular cactus does not adapt well to freezing temperatures and tends to go dormant in the winter.

Planting and potting

Most succulent growers plant the old man cactus in a pot (preferably terracotta) and leave it outside during the summer and spring seasons where it can soak up its fill of sun.

When winter rolls back around, they carry the pot indoors and place the succulent under grow lights as a substitute for sunlight.

Sunlight stimulates the growth of Cephalocereus senilis’ long silver hair. The more sun it soaks up, the thicker and longer its silver hair gets.


The old man cactus is prone to the occasional nasty critter here and there because its long shaggy strands of white hair provide a perfect environment for these pests to hide and nestle in.

Something similar to how lice love to hide in long unkempt hair.

Look out for mealybugs, spider mites, and scale.


Re-potting this particular cactus shouldn’t be a concern, especially when you factor in its slow growth rate – the  Cephalocereus senilis grows even slower when potted indoors compared to out in the wild.

Common practice is to gently loosen the soil around the roots and slowly work the cactus out of the pot.

Inspect the root system – when you notice the roots wrapping themselves around the bottom of the root ball, then it is about time to move this succulent to a new, slightly larger pot.

Where to find Cephalocereus senilis ?

Ask the supervisor down at your local gardening store whether they stock  Cephalocereus senilis seeds.

Home Depot and Lowe’s pack an extensive range of succulents and cacti for sale.

Swap meets and flea markets remain our favorite places to go succulent shopping.

We highly recommend you visit these open-air markets. They are the perfect place to source obscure succulents of all kinds at pocket-friendly prices.

If you’re unable to leave the house for whatever reason (ahem, coronavirus, ahem), then you can opt for online shopping:

  • Buy the Cephalocereus senilis from Etsy for $22.36


Check out our Succulent City Facebook page and share pictures of your old man cactus with fellow succulent lovers from across the globe!

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