A “false saguaro” is a broad term for various columnar cacti that visually resemble the iconic saguaro, Carnegiea gigantea, but belong to different botanical species. These plants are popular in arid landscaping, offering a desert aesthetic. They are often chosen for their architectural form and ability to thrive in dry conditions.
Identifying the False Saguaro
The term “false saguaro” encompasses several columnar cacti that mimic the saguaro’s towering, ribbed appearance. These plants typically exhibit an upright, tree-like growth habit, often with multiple stems emerging from the base or lower sections.
One common example is Pachycereus schottii, known as the Senita or Totem Pole Cactus. The Senita cactus forms clumps of numerous columnar stems, often branching at or near the base, and can reach heights of up to 13 feet. Its mature stems are distinguished by hair-like bristles at their tips, and some forms, like the ‘monstrosus’ cultivar, are spineless with knobby, irregular stems.
Another example is Cereus hildmannianus, commonly called the Peruvian Apple Cactus or Hedge Cactus. This species grows like a candelabrum with numerous columnar branches and can reach heights of 30 feet or more. While Cereus hildmannianus often has smooth, nearly spineless stems, some subspecies can be spiny. Its stems are blue-green to dull green, segmented, and feature four to six ribs. Pachycereus pringlei, the Mexican Giant Cardon, is another false saguaro. This cactus is known as the world’s tallest, with some specimens reaching over 60 feet, and develops numerous arms or branches as it matures.
Key Differences from True Saguaro
Distinguishing between a true saguaro (Carnegiea gigantea) and its “false” counterparts involves observing several key characteristics. True saguaros typically develop their distinct upward-curving arms higher up on the main trunk much later in their lifespan, often after 50 to 75 years of growth. In contrast, many false saguaros, such as Pachycereus schottii and Cereus hildmannianus, often branch from the base or lower down on the stem, creating a more candelabra-like shape from a younger age. The Mexican Giant Cardon (Pachycereus pringlei) can also branch from the base or have a single, massive trunk with branches.
Spine characteristics also vary. True saguaros possess stout, rigid spines arranged in clusters along their ribs. Many false saguaros, like Cereus hildmannianus, are often spineless or have very short spines. Pachycereus schottii has hair-like bristles on its mature stem tips, and its ‘monstrosus’ form is spineless. While saguaros have prominent ribs, their number typically ranges from 12 to 30. False saguaros like Pachycereus schottii usually have 5 to 9 ribs, and Cereus hildmannianus commonly displays 4 to 6 ribs.
Regarding flowers and fruit, true saguaros produce white, nocturnal flowers near the tips of their stems, followed by red, fleshy, edible fruit. Pachycereus schottii has light pink, nocturnal flowers that also produce edible red fruit. Cereus hildmannianus produces large, white, nocturnal flowers and edible, pinkish-red fruit. The Mexican Giant Cardon also blooms with large, white, nocturnal flowers. In terms of size and growth rate, true saguaros are slow-growing, taking decades to reach their mature height of 40-60 feet and living for over 150 years. While false saguaros like the Mexican Giant Cardon can exceed 60 feet, they are also slow-growing but can sometimes grow faster than saguaros in cultivation.
False Saguaro Care
Caring for false saguaros involves providing conditions that mimic their arid native environments. These columnar cacti thrive in full sun exposure, ideally receiving at least six to eight hours of direct sunlight daily. While some can tolerate partial shade, insufficient light can lead to etiolation, where the plant stretches and becomes pale. False saguaros require well-draining soil to prevent root rot, a common issue for cacti. A sandy, gravelly, or specialized cactus potting mix is suitable, often amended with perlite or coarse sand.
Watering should be infrequent but thorough, following the “soak and dry” method. During the active growing season in spring and summer, water deeply, then allow the soil to dry completely before watering again, typically every two to three weeks. In fall and especially during winter dormancy, reduce watering significantly, as some species may require no water at all. False saguaros are generally drought-tolerant once established. Most false saguaros are not frost-tolerant, with many varieties requiring protection when temperatures drop below 25-40°F ( -4 to 4°C). If growing in colder climates, cultivate them in containers so they can be moved indoors or protected during winter. Fertilization needs are minimal; a balanced, diluted cactus fertilizer can be applied once a year during the growing season, but over-fertilizing should be avoided.
Uses and Other Considerations
False saguaros are valued for their architectural presence in landscape design, particularly in desert gardens and xeriscaping. Their upright, columnar forms create vertical accents. These cacti are often used as focal points in rock gardens, along sunny slopes, or as standalone specimens in spacious yards. Their silhouettes and branching patterns add visual interest and structure to outdoor spaces.
Many false saguaros are suitable for container planting, especially when young or in climates where they need winter protection. When grown in pots, they can bring a touch of the desert indoors or onto patios. Most common false saguaro species are considered non-toxic, making them generally safe for landscapes where pets or children may be present. While some species, like Cereus hildmannianus, produce edible fruit, their primary use in cultivation is ornamental. These plants are known for their longevity, often living for many decades or even hundreds of years.