The columnar cactus, also called Cereus, is very popular in the room because of its striking appearance. Since it comes in numerous species, it is not always easy to determine the exact variety. However, there are a few characteristics that can help you identify a columnar cactus quite well.
How to identify a columnar cactus?
To identify a columnar cactus (Cereus), look for upright growth, single or multi-stemmed form with ribbed trunks, presence of thorns and night blooms. Columnar cacti differ from leaf cacti in their shape, thorns and flowering behavior.
Characteristics for identifying the columnar cactus
- Upright growth
- single-stemmed or multi-stemmed
- Trunks with ribs
- almost always armed with thorns
- only blooms at night
The columnar cactus comes from South America. It only needs a little water because it can store the moisture in the trunk.
In its homeland, a columnar cactus can grow to more than 15 meters high, depending on the species. When grown indoors, with good care it reaches a height of one meter or more within about six years.
Upright shape with one or more trunks
The columnar cactus always grows in an upright form. Some varieties have a main stem with no secondary shoots, while others form multiple stems.
The individual trunks are ribbed, the number of which varies depending on the variety. There are species that only have seven to eight ribs, while others have up to 30 ribs.
Difference to leaf cactus
Leaf cacti are succulents. They are at home in the rainforests and in nature almost always grow on the leaves of other plants. Their shoots consist of several limbs that hang down. This makes the leaf cactus well suited as an hanging basket plant. Thorns are almost never present, while the columnar cactus always has thorns. These can sometimes be very pronounced.
Leaf cacti, which include Christmas cactus and Easter cactus, bloom regularly when kept cooler in winter, unlike columnar cactus. Some varieties also require several hours of complete darkness per day.
The columnar cactus almost never blooms when grown indoors. The gardener will have better luck if he can grow the Cereus in the greenhouse all year round. However, the flower is only open at night. It fades quickly during the day.
Tip
When repotting a columnar cactus, be careful. The roots are very sensitive and should not be damaged if possible. Sick and injured roots increase the risk of disease.
