Everything You Didn’t Know About the Star Cactus—Astrophytum Asterias

The Star Cactus

By now we’re pretty confident you know a lot of succulents and cacti, unless you’re new here! Stick around, you’ll learn a lot.

Though we’ve brought a lot of knowledge to our community about succulents, we’re lacking a bit in the cactus department, there is still a lot to talk about in terms of the available species. Really, there’s just as many cacti as the larger succulent group. And the star cactus is a proud member here.

the star cactus
star cactus @about.plants

The Star Cactus—Astrophytum Asterias

Scientific Classification

As with many cacti, the Star Cactus is part of the cactaceae family similar to the very interesting brain cactus we’ve written about before. Further down classification, this cactus is a member of the Astrophytum genus, whose members are cherished for their flowering property. Every plant lover likes a beautiful flower from time to time right?

In the botanical world, the Star Cactus is referred to as Astrophytum Asterias. In common terms, it has quite a number of names apart from the one above, see them below.

  • Star Peyote
  • Sand Dollar Cactus
  • Sea Urchin Cactus

Origin of the Star Cactus

Just like most cacti, the Star Cactus is endemic to… can you guess?


the star cactus
here comes the sun @ixim00

Characteristics of the Star Cactus

Star Cacti are small round plants with the height usually ranging from 1 to 2 inches and the diameter being anywhere from 2 all the way to 6 inches. The plant is usually green in color with an occasional tinge of brown on some.

The whole globular stem is a ribbed structure with the number of ridges being as many as 10, sometimes more. Each rib is dotted with white hairy areoles.

The flowers are yellow with a combination of other colors – orange and red – that take up the centers and the bases respectively. These blooms typically appear in between the months of March and May.

In late spring, these flowers turn into oval woolly berries that can be green, gray, pink or reddish.

the star cactus
star cactus garden @greenstonebotany

How to Take Care of the Star Cactus

Being a succulent, the Star Cactus can do just fine with minimal care like most succulent houseplants out there. Even when your plant nurturing abilities are just catching on, you’re sure to be fine with this jewel.

Have a look at the little things you need to do for a nice Star Cactus plant thriving in your home.

Ideal Temperature

The star Cactus is quite hardy, as far as how low the temperatures can get. This baby can brace readings as low as 20°F ( -6.7°C). The higher limit for its survival is 50°F (10°C).

Light Requirements for the Star Cactus

Sunlight is a favorite among many cacti, it’s no wonder they thrive in the desert right? The Star Cactus especially loves the beaming sun light too.

Give your plant a few hours of direct sunlight on a daily basis and see it smile at you. In case your home cannot provide enough direct sunlight, check out indoor LED plant lights, like this one from Amazon perfect for smaller cacti like this.

the star cactus
shining star cactus @greenfingeredarchitect

Soil and Fertilizing Necessities

A well-draining soil mix is important for growing a healthy Star Cactus. A poorly drained one like the regular soil mix is a sure way of inviting rot. Though traditional plant soil is great, it’s not too healthy for cacti or succulents, since they thrive in different climates, their soil requirement is a tad different.

We highly suggest going for a quality commercial cactus and succulent mix— we’ve been recommending this one a lot and it’s been making the growing of our readers’ succulents and cacti much easier. This dries up in the required timeframe to give the roots the very much needed breathing space, something that traditional soil does not do.

Alternatively, fixing up your own well-draining mix is a viable option too, we’ve written a full article about it here or continue reading! Throw together parts of regular potting soil, pumice (perlite is great too) and coarse sand. Make sure the end product is the real deal by wetting and squeezing it. Coarse and crumby, that’s exactly what we’re looking for!

For fertilizing, supply your plant with a diluted houseplant fertilizer during the growing season (June to September). Forget about fertilizing during winter.

For some extra help on creating your own succulent soil at home, check out our helpful tips here!

the star cactus
star cactus blooming yellow flower @cosmicrootscacti

Watering the Star Cactus

Water may be an essential compound of life, but for the Star Cactus, it’s significance isn’t as much – that’s to say, compared to your average houseplant.

That is to say, you’ll still need to water your cactus but the number of times will be way much less. Depending on the environmental conditions in your area, 2-4 weeks apart is fine.

Essentially, you’ll want to water when the top part of the potting mix is dry. You can dig in with a finger to ascertain this.

During winter, cut back further on this watering as the plant is mainly dormant. Once or twice watering for the whole of the cold season will serve the plant just right.

the star cactus
star cactus producing white flower @kate_rouh

How to Propagate the Star Cactus

The Star Cactus has one sole propagation method: seedshere’s some inexpensive seeds we’ve used to grow some in the office. One thing you have to note is that the seeds need to be planted as soon they’re harvested to boost the chances of them forming new plants. Be quick!

Fill up a seed flat, like this one with an endless amount of cells, with well-aerated soil and cast the seeds. Remember to keep the soil moist from germination up to the point when they’re ready for transplanting – ideally half an inch tall.

When the sprouts are apparent, move them to a well-lit spot. Beware though! Don’t let them come into contact with the afternoon sun, provide some shade once in a while.

Also, overhead watering is a no-no. Settle for wetting the soil to avoid damaging the tender young star cacti. You can use a watering bottle like this to ensure you’re not damaging you’re precious cactus.

the star cactus
cute star cactus planter @succustories

Repotting the Star Cactus

Repotting is a mandatory activity— at least if you cherish a nicely growing plant, and who doesn’t? Everyone, including plants, need a new home once in a while!

In 2-4 years, repot your star cactus to a new pot, like these unique stone pots, that matches its size requirements. This gives the roots an abundant access to fresh air. The whole plant will sing you a song for that.

Just be sure to repot at the beginning of a growing season and give the plant some time before you start the regular watering and fertilizing.

Need some tips on repotting your cactus plant correctly, we’ve helped a lot of readers here, be sure to comment if it helps you too!


the star cactus
soakin’ up the sun @cosmicrootscacti

The Star Cactus’ Enemies & Potential Problems

The star cactus is likely to be attacked by the common cacti-loving insects around like mealybugs, mites and scale.

Many succulents and houseplants in general are prone to pests of all sorts. Continue reading so you can defeat these pests for the health of your star cactus. We can’t let these bugs win all the time!

Defeating Mealybugs

Usually show up as white tiny fuzzy looking things – more like small cotton wool balls. They slowly diminish the plants vigor by sucking its sap like a vampire.

On the bright side they don’t take much to get rid of.

Just spray your plant with a jet of water and… off they’ll go. Alternatively, rubbing alcohol and water can do it. Use a piece of cotton to apply this mixture on the affected areas. If you’re interested, more details on how to defeat mealybugs here, we’ve actually helped hundreds of people already.

In addition to sucking on the sap, mealybugs can also munch on your plant’s roots in the worst case. Here, you’ll notice the plant becoming unhealthy even when everything appears to be fine above the surface. Of course we’ll have to remove the plant from the potting mix and check the roots. If you notice the tiny beings, give the roots a good shower and repot in a new pot (or wash the previous one thoroughly) using fresh potting mix.

the star cactus
perfect soil @cosmicrootscacti

Finding Mites

The fact that they’re attracted to the same conditions as cacti makes them particularly a troublesome lot. And they’re quite good at playing hide and seek, so you may not be able to notice them until your plant has been hit hard. Brown patches are a sure sign of their presence.

To kick them off, just use the wash technique above or give them a dose of rubbing alcohol mixed with water. It will serve them right!

Unwanted Scale Bugs

Scale bugs typically have a tough outer covering and hide beneath it as they munch on your cactus. And they can’t be washed off as easily like the two pests above. You have to go at them on a one-by-one basis using good ol’ rubbing alcohol and water.

Avoiding Root Rot in Star Cacti

This is a sure problem if the plant is getting too much water or the soil mix isn’t draining fast enough. Which is why we stress the importance of a high quality draining soil mix like we mentioned above. Here it is again if you need it for reference.

So, be sure to check on how much you’re watering and what type of soil mix you’re using to avert this.

the star cactus
star cactus family @succy_bonsaii

Where Can I Buy the Star Cactus?

With the immense popularity of succulents, and the Star Cactus itself, having your own plant is as easy as walking into your local nursery. They’re sure to have it.

Or you can have the babies delivered to you by placing an order online. There are so many online stores that deal in succulents and looking up star cactus is going to yield all you want. Start off with the following:

  • Amazon
  • Mountain Crest Garden
  • Succulent Box
  • Etsy
  • Leaf and Clay
the star cactus
the star cactus @i_loph_it

What do you think? Looking to add these little gems to your cactus garden? Show us your photos in our exclusive Facebook group, Succulent City Plant Lounge!

Also if you don’t know yet, as we continue to collaborate with Amazon.com, we’re able to offer 2 free audible books to our readers when signing up through here. Our office is filled with people listening to their books rather than music (although music is nice sometimes). Let us know what books you decide to listen too!

Happy planting! ?

Calling all succulents lovers— rookie or veteran! Succulent City has developed a line of 12 ebooks (see here), ranging on topics from indoor & outdoor succulents, essential tools, the best soil to use, and more! We even threw in a complimentary ebook to help get your succulent journey started you just have to insert your email on our front page for this. With our ebooks you’ll be a succulent guru in no time, have fun!

Haworthia Retusa

Haworthia Retusa – Detailed Care Guide

Haworthia retusa is also called Star Cactus. Even though it is called “Star Cactus,” Haworthia retusa is a soft window succulent with translucent leaves and not a cactus plant.

haworthia retusa
Haworthia Retusa @Amazon

Star Cactus is native to Western Cape Province, a small town in South Africa. The natural environment of Haworthia retusa is a low, flat terrain.

Not only has Haworthia retusa won the hearts of millions of succulents growers around the world, but it has also won the Award of Garden Merit put together by the Royal Horticultural Society in the United Kingdom.

This article is all you need if you would like to know how to propagate and care for the Haworthia retusa.

Description of Haworthia Retusa Succulents

Haworthia retusa is a small succulent that does not grow beyond six inches in diameter. The lime green leaves of the succulent form rosettes and have translucent windows on the tips. The leaves measure approximately three inches in length and an inch in width.

The Star Cactus produces flowers with brown or green veins when it blooms in the summer or spring.

Haworthia retusa is not poisonous to pets and humans, so you can grow it indoors.

Caring for Your Haworthia Retusa Succulents

It is not difficult to please the Haworthia retusa succulent. It will survive indoors or outdoors as long as it can get an ample amount of sunlight and water. Here are some factors to consider when growing your Haworthia retusa plant:


For your Haworthia retusa to thrive indoors, it needs to be kept close to bright light. You can place the succulent pot close to an east or west-facing window to get the desired amount of light.

If you don’t have a well-lit home, the Haworthia retusa will stretch in the direction of light and become leggy. To prevent this, you should supplement your indoor lighting with a grow light.

If you are growing your Star Cactus outdoors, it would be best to plant it in a succulent pot rather than in the ground. If the weather becomes inclement, you can easily move the pot inside. Also, you can move the pot to get as much sunlight as possible.

The Star Cactus plant is better off under partial shade. But it can withstand full sun when there is no heatwave. Full sun and high heat levels can lead to sunburn and dehydration. To prevent sunburns, ensure you acclimate your succulents to full sun. About three to four weeks need to pass for the Haworthia retusa to adjust to full sun fully. But then, if your Haworthia retusa is already sunburned, the only thing you can do is to either trim off the damaged parts or allow the damaged parts to be replaced with fresh parts.


Just like most succulents, Star Cactus should not be overwatered or left in standing water to avoid root rot.

To prevent overwatering, ensure you examine the soil before watering. Stick fingers into the soil and feel the moisture content of it. For better testing, use a moisture meter to determine the moisture level of the soil.

If the soil is moist, wait for a couple of days for the soil to dry before watering again. When you allow the soil to dry before resuming watering, the natural environment of the succulent is simulated, allowing the plant to grow healthy.

Note that Haworthia retusa succulents are usually dormant during the summer. In light of this, ensure you water them just enough to prevent the leaves from drying up. During the fall, when the succulent is actively growing, you can continue your regular watering schedule.

Star Cactus can thrive in fairly high humidity. If you live in an environment with a dry climate, you do not have to bother about getting a pebble tray or humidifier to adjust the humidity level.

But then, you need to water these succulents more frequently in high humidity. The rate of evaporation will drop during this period and the soil will remain moist for longer than usual.


Haworthia retusa cannot withstand frostbite, so you must protect it from icy temperatures. While this succulent is happy with cooler temperatures in the winter, ensure you do not expose it to freezing temperatures.

Haworthia retusa can thrive in a temperature range of 30 to 50 degrees Fahrenheit. If the temperature is below that range, you risk killing your plant to freezing. On the other hand, if the temperature is above that range, your Haworthia retusa succulents may suffer from sunburn.

You should consider moving your Haworthia retusa succulents indoors during the winter months, where the temperature is warmer and stable.


Star Cactus cannot survive for long in wet soil. Hence, it would be best to avoid potting mix containing water-retaining ingredients such as peat moss, coconut coir, or clay. If the soil drains quickly, small portions of these ingredients will not be that harmful.

To enhance the drainage of the soil, use large particles of perlite, gravel, and coarse sand. These ingredients permit airflow to the roots of the succulents when the soil dries up.

While succulent pots with drainage holes help the soil to dry out quickly, your succulents can still survive in a pot with no drainage holes. You just have to know how to water the succulents properly and examine the soil’s moisture level.

How to Propagate Haworthia Retusa Succulents

Haworthia retusa is quite easy to propagate. It is best to propagate this succulent when it is actively growing, so the new plants can have enough time to develop before their dormancy period. Here are the ways to propagate Haworthia retusa succulents:


Propagating Star Cactus plants from seeds require patience because seeds take time to germinate. But the process of experimenting is quite fun for succulent growers.

Plant the seeds in a damp, warm soil. If these soil conditions are not met, your succulent seeds will not germinate. You can use a seed tray to cover the soil, so the seeds will always be warm.

After about three or four weeks, you will notice that the seeds are germinating. At this stage, you can remove the seed tray.

Ensure that the soil is not overwatered to prevent root rot. You can adopt the “wet and dry” watering technique that involves watering and waiting until the soil is dry before resuming your watering schedule.


If you got no patience to wait for seeds to germinate, you can opt for propagating by stem or leaf cuttings. This is a more effective method of propagating Haworthia retusa.

To propagate from leaf or stem cuttings, cut off a mature stem or leaf with a sterilized knife. Allow the cuttings to dry for a couple of days, so the cuts can heal. This helps to prevent infectious organisms from attacking the cuttings when they are planted.

After sticking the cuttings in the soil, do not water until you notice tiny roots springing up. If you want to speed up the root development process, dip the cuttings in a rooting hormone before sticking them in the soil.

You can water and care for the cuttings the same way you would care for a mature succulent as soon as you notice the tiny roots appear.

Bear in mind that planting a number of cuttings in a single pot will give you a vibrant array of succulents when the cuttings mature, so you should consider taking more than a handful of cuttings for propagation.


Propagating Haworthia retusa by offsets is the easiest way to go. If you follow the watering, lighting, and temperature conditions mentioned above, your Haworthia retusa will produce offsets in no time.

You can cut off these offsets with a sterilized blade or pluck them from the plant with your fingers. Ensure you go as close as possible to the parent plant when cutting off the offsets. This will help the offsets in forming roots quickly and increase their chances of survival.

Plant the offsets in a different pot and nurture them the same way you would nurture a mature succulent.

Common Pests and Disease Problems Associated with Haworthia Retusa Succulents

Perhaps, the most difficult aspect of caring for the Star Cactus plant is watering. The chances of survival for the Haworthia retusa succulent are quite slim if it is overwatered. Hence, it is very important to check the moisture level of the soil regularly.

If the roots of this succulent start to rot due to overwatering, it will be pretty difficult to save the plant. If the roots are not yet damaged, but the leaves are becoming mushy or yellow, you can still save the succulent by removing the excess water from the pot.

To remove excess water your succulents are standing on, hold the soil with one hand and flip the container with your other hand. If the water is not that much, you can move the pot to a dry, sunny area so that the excess water will evaporate.

In a bid not to overwater your Haworthia retusa succulents, ensure you do not under-water them. If you notice that the leaves of the Star Cactus have a wrinkly or shriveled appearance, take that as a sign to up your watering game.

When it comes to pest attacks, keep an eye out for fungus gnats, spider mites, and mealybugs. Ensure that there is no decaying material in the soil that will attract these pests. Also, insecticides can help to get rid of these pests, especially at the early stages of infestation.