Euphorbia grandicornis is commonly known as the cow's horn cactus, rhino thorn, or the big horn. It belongs to the Euphorbiaceae family and is native to a few places, including South Africa, Switzerland, and Kenya. Growing up to a height of 1.5-6.5 feet , this multi-stemmed shrub goes dormant in winter.

Growth Rate

The Rhino Thorn is a relatively fast-growing cactus, and it stays content in its position and with its soil for many years.

Flowering

The Euphorbia grandicornis cow's horn cactus flowers are produced between spine pairs on newer growth, restricting them largely to the branch tips. These flowers are yellow and golden.

Watering and Feeding

Euphorbia grandicornis grows actively from the spring to the fall season, and that is when it should get the right amount of water. You can add a little bit of organic fertilizer to a young plant so that it grows healthily.

Soil

While any commercial succulent potting mix will keep the succulent happy, you can also create an organic Cow's Horn Cactus soil mix with 50% potting soil and 50% regular soil.

Hardiness

You will need to ensure that the air is at least 50 percent humid throughout the year since the plant has a hardiness zone of 10a to 11b. It can withstand temperatures up to -1.1°C.

Light

The Cow's Horn Cactus Euphorbia grandicornis light requirements include direct sunlight for at least six hours on a daily basis. If you plan to grow this plant indoors, you must place it near a window that gets lots of sunlight.

Propagation

Stem cuttings are the easiest way to propagate your Euphorbia grandicornis. Get a clean and sharp knife and collect the cuttings near the plant’s branching point.

Pinch out the tips of the plant occasionally as this will help encourage thicker growth. Other than pinching, plants need no particular grooming tasks.

Some of the information in this description has been found at desert-tropicals.com, llifle.com and cactus-art.biz