Having become one of the most popular house plants, often because of their purported ease to care for, there’s another reason to appreciate these funky plants. In contrast to their globular shapes and spikey flesh, cactus flowers display an unparalleled beauty. Beyond the aesthetic appeal, cactus flowers also provide necessary food for hummingbirds, bats, bees, and other pollinators. While cacti have spread in horticultural popularity around the globe, they are native to the New World.
What Are Cactus Flowers?
Cacti all fall under the succulent category, but not all succulents are technically cacti. To be a cactus, the plant must develop a particular type of flower including the:
- Many interwoven tepals (includes both petals and sepals)
- Hundreds of stamens (the male part of the flower)
- Multiple lobes on the stigma (the female part of the flower)
If a plant lacks such a flower, it cannot be a cactus. Additionally, cacti are delineated from other succulents by the presence of areoles, which are small bumps along the stem where the spines grow. Often mistaken for cacti, aloes, euphorbs, and agaves fall under different plant families. Here we’ll take a closer look at some of the cactus species that produce the most beautiful cactus flowers.
Subtle and Surprising: Gymnocalycium
Though an intimidating word, Gymnocalycium is a genus of cacti that often don’t have common names, so we’ll stick with the laborious Latin. The most commonly recognizable plant in the genus is the moon cactus, which is notable for its ability to grow without chlorophyll, and when grafted to another cactus, become a brightly colored cactus hat. But as far as remarkable flowers go, the G. anisitsii has all its cousins beat.
Native to the Tucavaca Valley in Bolivia, G. anisitsii sports a few unique growth patterns. Usually, cacti are thought to be a sun-loving bunch, and many are (think the blazing deserts of southern Arizona). The G. anisitsii, however, prefers more shady areas, and will even find its home nestled under the cover of shrubs. When it’s not flowering, G. anisitsii isn’t much to see. Its low, lumpy base is a muddled mixture of olive to brownish purple, with less than impressive spines that don’t do much for protection.
Lucky for the cactus lovers of the world, this species rarely has a moment when it’s not flowering! It’s even known for flowering when it’s very young, sometimes producing flowers when only 1.5 cm in diameter. With petals that are delicate and pink, the cactus flowers of the G. anisitsii trumpet out from the base into a firework of petals. They remind many of lilies.
The Most Hipster Cactus Flower: The Fishhook Cactus
A classic of the American Southwest, the Fishhook Cactus (Mammillaria dioica) is charming as can be! With rotund, barrel-shaped forms, this cactus loves to live in gravelly washes in Arizona and Northern Mexico. The cactus is named for the shape of its spines – instead of coming to a straight point, they curl back at the end like a fishhook.
While these charismatic cacti usually grow to be a couple of feet tall and a couple of feet in diameter, they can reach heights up to eight feet and be four feet around. That’s a chunky cactus! But it’s no surprise they have time to reach these mammoth sizes. Fishhook barrel cacti are some of the longer-lived species of cacti, with lifespans of up to 100 years. As they grow taller, they often lean toward the sun (a phenomenon called phototropism), and many of these cacti end up growing to the Southwest, giving them the appropriate nickname “Compass Cactus.” They sometimes lean far enough to uproot themselves.
While there are plenty of reasons to love the Fishhook Cactus, the flowers are the real sell. From rich reds to creamy pinks, the flowers even come with striated petals. But the fishhook cactus stands out with its flower crown. Though each cactus flower is individually small, they bloom in a circle around the top of the cactus, putting all the Coachella attendees to shame.
A crown of Fishhook cactus flowers. Image by US Fish and Wildlife Service via Wikipedia // Public Domain
The Most Festive Flower: The Christmas Cactus
Another funky Latin name, the genus Schlumbergera includes cacti that sport gorgeous flowers. Though they look remarkably different from the Saguaros and Barrel Cacti in the American Southwest, Schlumbergera meets the criteria to be in the cactus family. More recognized by their common names, Christmas Cactus (Schlumbergera bridgesii) has long segmented branches that end in gorgeous blooms around their name-sake holiday.
The Christmas Cactus flower is where things get interesting. The petals fountain out from the end of each branch, layering over each other to give the appearance of two flowers stacked on top of one another. Ranging from pinks to reds, the flowers are also striking in their neon pink stigma. With their tubular shape and brilliant coloration, it’s no surprise that the flowers target hummingbirds as their pollinator of choice.
The Most Magical Cactus Flower: Epiphyllum oxypetalum
Having earned its way to the “Most Magical” superlative, this cactus has quite a bit of mystique to uphold. But, with a common name like Queen of the Night, we’re sure it fits the bill. First, the Queen of the Night is an epiphyte, meaning it grows on the surface of other plants, and derives its nutrients from the air and rainwater. Native to South America, it has deservedly become a popular houseplant and is widely cultivated.
With long, branching stems, the entire plant is quite graceful, though the flowers hold the real mysticism. Both beautiful and fragrant, the Queen of the Night flowers bloom only for a single night in the summer. Similar to most night-blooming flowers, the Queen of the Night forgoes bright colors for a creamy white. To attract pollinators, it instead relies on its sweet smell. With up to 30 petals that reach six inches in diameter, this large flower could easily dress a fairy.
The Least Cactus-like Plant: The Rose Cactus
With its true leaves and tree or shrub-like growth pattern, plants in the genus Pereskia look nothing like what is usually thought of as a cactus. However, because their spines develop from areoles and their distinctive floral cups, they can be classified in the cactus family. Additionally, many of the plants in the genus sport some pretty magnificent flowers. For example, the Rose Cactus (Pereskia grandifolia) is notable for growing many flowers at once, clustered at the ends of branches. The gradient of pastel pink to white, leading into a yellow center is reminiscent of a true rose flower. Interestingly, the fleshy leaves of the cactus are edible and can be cooked or eaten raw on salads.
Along with their charming shapes and ease of care, many cacti have gorgeous flowers. But as much we celebrate these species, we should also give care to their conservation. According to a global species assessment by the IUCN (International Union for the Conservation of Nature), 31% of cactus species are threatened with extinction. Because of increased demand for cactus plants, illegal trade and unsustainable harvesting for horticulture and private collections continues to pose obstacles to cactus conservation across the globe.
But appreciating these amazing plants still can bring rays of delight to everyone! If you are lucky enough to visit an ecosystem where cacti grow or even grow one of these beautiful flowering cacti on your windowsill, try to identify them. You can use a helpful app like PlantSnap to figure out which species you see.
Featured image by US Fish and Wildlife Service via Wikipedia // Public Domain