The question of whether the ZZ Plant (Zamioculcas zamiifolia) is a succulent is a common point of discussion among plant enthusiasts. From a botanical perspective, the answer is nuanced. While it is not taxonomically classified as a true succulent, it possesses and employs many succulent-like adaptations, leading to its frequent categorization as such in horticulture.
First, it is crucial to distinguish between strict botanical classification and functional morphology. True succulents belong to various plant families, such as Cactaceae (cacti) and Crassulaceae (e.g., jade plants), and are defined by their ability to store water in specialized tissues in their leaves, stems, or roots. The ZZ Plant, however, is a member of the Araceae family, which includes plants like peace lilies and philodendrons. Taxonomically, it is not grouped with typical succulents. Despite this different lineage, the ZZ Plant has evolved similar survival strategies in response to its native arid environments in eastern Africa. It is therefore more accurately described as a "drought-tolerant" plant that exhibits "succulent characteristics."
The ZZ Plant mirrors true succulents through several key physiological and morphological adaptations. Its most prominent feature is its rhizomes. These thick, potato-like structures grow underground and serve as massive water and nutrient storage organs. During periods of drought, the plant draws upon these reserves to survive, which is a classic succulent strategy. Furthermore, its leaves are exceptionally thick, waxy, and glossy. This cuticle layer significantly reduces water loss through transpiration, much like the leaves of many succulents. The leaflets (pinnae) are also fleshy, containing parenchyma tissue that can hold moisture.
While the adaptations are similar, some differences highlight why it is not a true succulent. Many true succulents utilize a specific form of photosynthesis known as Crassulacean Acid Metabolism (CAM). CAM photosynthesis allows plants to open their stomata at night to take in carbon dioxide, minimizing water loss during the hot day. The ZZ Plant does not utilize CAM photosynthesis; instead, it employs a standard C3 pathway. However, it compensates for this with its incredibly efficient water retention via its rhizomes and waxy leaves. Its growth pattern and reproductive structures (a spadix typical of the arum family) are also distinct from those of most succulents.
From a care and cultivation standpoint, treating the ZZ Plant as one would treat a succulent yields the best results. Its primary requirement is excellent drainage and infrequent watering, allowing the soil to dry out completely between waterings. Overwatering is the quickest way to cause root and rhizome rot, a common issue with true succulents. Its low light tolerance and slow growth are also traits it shares with many succulent species, making it an ideal choice for similar indoor environments.
