The Zamioculcas zamiifolia, commonly known as the ZZ Plant, is a resilient and popular houseplant. Its striking, waxy, deep-green foliage makes it a favorite for adding greenery to homes and offices. Originating from the dry grasslands and forests of tropical East Africa, the plant’s natural habitat dictates its need for warm temperatures and explains its limited cold tolerance.
Understanding Hardiness Zones
The USDA Plant Hardiness Zone Map provides a standardized framework for gardeners to determine which perennial plants can survive winter outdoors. This system divides North America into zones based on the average annual minimum winter temperature. Zones range from 1 (coldest) to 13 (warmest), with each zone representing a 10-degree Fahrenheit difference in the minimum temperature range.
Knowing your hardiness zone helps gauge a plant’s ability to live outdoors year-round without protection from the cold. For instance, a plant rated “hardy to Zone 7” is expected to survive the typical minimum winter temperatures of that zone. The map focuses solely on cold tolerance and does not account for other factors like soil type, summer heat, or local microclimates.
ZZ Plant’s Outdoor Survival Range
The ZZ Plant is a tropical perennial that can only survive year-round outdoors in the warmest regions of the United States. It is generally considered winter-hardy in USDA Zones 10 and 11, though some sources extend this range through Zone 12. This means the plant can tolerate lowest average annual temperatures corresponding to 35°F to 50°F.
Its native range spans from Kenya south to northeastern South Africa, a region characterized by consistent warmth. The plant’s survival is compromised by cold temperatures outside of this tropical climate. While the plant can tolerate a brief dip to about 45°F, exposure below 50°F can cause discoloration and reduced growth. The presence of frost or any temperature below freezing (32°F) is lethal to the plant’s tissues, making year-round outdoor cultivation impractical for most areas.
Why ZZ Plants Thrive Indoors
Since most regions fall outside of the necessary Zone 10 and 11 range, the ZZ Plant is nearly always cultivated indoors, where it excels. The plant’s indoor success is linked to adaptations developed in its East African homeland. It is a rhizomatous plant, meaning it grows thick, potato-like rhizomes underground that function as water storage organs.
This specialized structure allows the plant to endure long periods of drought, making it tolerant of infrequent watering common in indoor care. The ZZ Plant thrives in the typical indoor temperature range, ideally between 65°F and 80°F. Its tolerance for low light is another advantage in homes and offices, though it grows best with bright, indirect light.
This combination of drought tolerance, low light adaptability, and preference for mild indoor temperatures makes the ZZ Plant suitable for interior spaces. Its slow growth rate and modest needs allow it to flourish where many other plants would struggle to survive.