Melocactus Ernestii | A Cactus With A Weird Head |

Melocactus ernestii cactus are endemic plants to Brazil. Usually, they would form at altitudes of 200 -1100 m above sea level. 

Their natural habitats would usually be rocky outcrop and granite areas. They are commonly called Melocactus. 

The highlight of these plants is their green stem which is covered by the long brown stems. Melocactus ernestii cactus is a flowering plant and many people tend to grow them due to that characteristic. 

melocactus ernestii

These plants would suit the experienced gardeners more as they would require somewhat difficult maintenance. 

If you are a succulent lover who wishes to start growing the Melocactus ernestii cactus, I urge you to read this article as this is a comprehensive guide as to how you should grow them.   

How do I identify Melocactus ernestii?

They are one larger Melocactus variety. Further it carries long spines as well. You could spot the matured Melocactus ernestii cactus carrying a cephalium. 

That would carry wool and bristles. On the other hand, the immature cactus would tend to take a barrel shape and you can hardly tell that they are melocactus.

The stem would either be spherical or depressed conical. Besides, they may also be either ellipsoid or short cylindrical too. 

They are light yellow green to dark green color. Those stems would reach a maximum height of 8-45 cm high and a maximum width of 7-25 cm.

Melocactus ernestii cactus flowers will arise from the cephalium. Moreover, they may carry about 9-13 ribs. They tend to take a round shape, Furthermore, chances are that you could spot them forming sharp edges as well.

To elaborate further on the cephalium, they would be more like either globose shape or shortly cylindrical shape. 

The cephalium would be about 2-18 cm high and 4-8 cm wide. The tightly peaked areoles would cover the cephalium. The areoles would contain pinkish red bristles. 

The areoles are rounded to obtuse in shape. They would form 1-2 cm apart. They may also carry red yellow bands. Further chances are that they would become gray or black as they mature.

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Melocactus ernestii cactus may carry 6-13 radial spines. They would be slender straight or form curving in an outward manner. 

They would be 4-15 cm in length. On the other hand, they may carry 3-8 central spines as well. 

Above all, as mentioned in the beginning of the article, Melocactus ernestii cactus produce flowers also. Those flowers would be small. They would form in light to dark pink, magenta color.

They would be 17-30 mm in length and 7-18mm in diameter. They have a close resemblance with the Mammillaria flowers. 

Their flowering season would be in mid-summer. Flowers are diurnal and they would stay alive for a few hours during lunchtime. Only the 6-10 years old plants will start to flower.

Melocactus ernestii cactus produce a fruit item and they would be somewhat flattened around the tips of the fruit.

They would form in different sizes. Their size would vary from 1.5 to 4.5 cm long, 6-10 mm in diameter. You could spot them forming in deep pink to crimson red. 

Those fruits may also carry seeds and they would be : 1-1,3 mm long, 0,8-1 mm wide. They are somewhat tuberculate too.

Growth rate

They are a rapidly growing plants if you provide the best conditions.

One look care guide

Botanical NameMelocactus ernestii
Common NameMelocactus
Plant Typecactus
Mature SizeA maximum height of 45 cm ( 17 inches )
A maximum width of 35 cm ( 12 inches )
Sun ExposureFull sunlight to partial shade
Soil TypeWell draining
Soil pHNeutral
Bloom TimeSpring
Flower Colorlight to dark pink, magenta color.
Hardiness ZonesUSDA hardiness zones 9a-11b 
6.7 degrees Celsius ( 20 degrees Fahrenheit ).
Native AreaBrazil
ToxicityNon toxic
Average price 8 USD

melocactus ernestii

How do you take care of Melocactus ernestii?

Light Requirement

It is vital that you expose them to bright sunlight for the them to grow well

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Having said that, they do not require the bright sunlight as the other arid cacti require. If you expose them to bright sunlight, it will turn them to bronze in color. That is crucial for flower blossoming and for the heavy spine production of the plants.

Temperature and humidity

They are not cold tolerant plants. Literally they cannot even stand fairly cold temperatures

As such I recommend growing them in temperatures around 8-12 degrees Celsius. If you expose them to frost, chances are that you may even lose your Melocactus ernestii cactus. 

When you grow them in warmer temperatures, it would result in the best growth of the plants. 

Melocactus ernestii cactus cannot stand temperatures which are below them 12 degrees Celsius to 20 degrees Celsius during their dormancy.

Is it cold hardy?

They are not cold hardy plants.

USDA Hardiness Zone

Melocactus ernestii cactus are hardy in USDA hardiness zones 9a-11b ( 6.7 degrees Celsius ( 20 degrees Fahrenheit ).

Watering Requirement

Watering the them well is very important when it comes to taking care of them properly. 

They would perform well with typical watering. Literally , you should never let them sit in water and always get rid of the excess water from the pots. 

Ensure that you do not over water them at any given time as it could bring you so many harmful effects on the plants. 

Soil Requirement Type / pH

A porous soil mix which has fast drainage would be perfect for the Melocactus ernestii cactus. Consider growing them in a standard actus soil mix.

Pot size Potting and Repotting

I recommend growing the them in unglazed pots which have good drainage. Moreover, in terms of reporting the Melocactus ernestii cactus, I do not recommend doing it often. 

Instead, you need to repot them when they outgrow from the pots. Moreover, I recommend repotting them when you freshly purchase them from the stores. 

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Where to Plant

As aforementioned, you should fulfill the sunlight requirement of them to ascertain a healthy growth of the plants. 

Considering that, you need to choose a spot where the plants can absorb sufficient sunlight levels. 

Literally it should be a place where they can gain morning sunlight as well as filtered sunlight during the midafternoon. Additionally, if you constantly experience colder times, you need to grow them as indoor plants.

melocactus ernestii

Fertilizer and time of year

They do not have strong demand when it comes to fertilizers. However, I recommend light feeding during their active growing seasons.


Melocactus ernestii cactus produces flowers in light to dark pink and magenta colors. Those flowers would be 17-30 mm long and 7-18 mm wide. 

Those flowers are diurnal, and those flowers will stay in blossom for a few hours only. The plants need to be at least 6-10 years old to produce flowers.


Melocactus ernestii cactus are dormant winter plants.


Melocactus ernestii cactus are non-toxic plants.

Common bugs and illnesses

Melocactus ernestii cactus are prone to certain pests such as red spiders, mealybugs, scales etc. 

Having said that, if you practice the right growing tips, you can keep your precious Melocactus ernestii cactus pest free. 

Ideally if you grow them in a substrate which has good drainage and if you water them in moderate levels, it will help the plants to stay healthy and pest free. Over watering would lead to root rot.

melocactus ernestii

How to propagate Melocactus ernestii

You can propagate the Melocactus ernestii cactus by seeds only. You can sow them in a light sandy soil mix in February to March. 

I recommend covering the specimen with glass so that it would avoid the specimen drying out. Ensure that you maintain a temperature range of 18-22 degrees Celsius during this process.


I hope this article gave you a broader view of how to take care of the Melocactus ernestii cactus well, the issues they may come across and the modes of propagating them etc. 

So, I trust these care tips would be useful for you and that you are excited to cultivate the Melocactus ernestii cactus   

Credit to : Wadoo
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About author

I’m Dr. Chamika, As a hobby love talking about plants and showing you that taking care of indoor plants. My website is knowledge I’ve learned over the years and continue to learn about growing succulents. If you’re a succulent lover, then you have come to the correct place.