The Cardboard Palm, scientifically known as Zamia furfuracea, is a popular plant admired for its stiff, leathery leaflets resembling cardboard. Native to Mexico, this cycad is generally low-maintenance. However, understanding its tolerance to cold temperatures is important for its long-term health and survival, especially as seasons change.
Cardboard Palm Cold Tolerance
Cardboard Palms are hardy in USDA Plant Hardiness Zones 9 through 11, indicating their preference for warmer climates. While they thrive in temperatures generally ranging from 60 to 75 degrees Fahrenheit (15-24°C), they can tolerate brief dips below this range.
The Cardboard Palm begins to experience significant damage when temperatures drop below 20-25°F (-6 to -3°C). Prolonged exposure to temperatures below 20°F (-6°C) can lead to severe damage or even plant death. Younger Cardboard Palms are generally more susceptible to cold injury than mature, established specimens.
Protecting Cardboard Palms from Cold
Safeguarding Cardboard Palms from cold temperatures requires proactive measures tailored to their planting location. For plants growing directly in the ground, apply a thick layer of mulch, about 3 to 4 inches deep, around the base of the plant to insulate the roots from freezing temperatures. Before an anticipated freeze, thoroughly watering the soil is also beneficial, as moist soil retains heat more effectively than dry soil.
Covering the foliage with protective materials like burlap, frost cloth, or even old blankets can be draped over the plant to shield above-ground parts from frost and trap warmer air. For Cardboard Palms grown in containers, move them indoors to a protected environment. Garages, sunrooms, or bright indoor spaces near a window can offer sufficient protection from cold snaps. Regularly monitoring local weather forecasts allows for timely implementation of these protective measures.
Handling Cold Damage
If a Cardboard Palm has been exposed to damaging cold temperatures, visual signs of injury may become apparent, including blackened, mushy, or discolored leaves. It is advisable to resist the immediate urge to prune affected foliage directly after a freeze event. Instead, waiting until spring when new growth begins to emerge allows for a more accurate assessment of the full extent of the damage.
Once new growth is visible, dead or severely damaged fronds can be carefully removed. Prune these affected parts by cutting back to healthy tissue, using clean, sharp tools to prevent further stress or disease. Even if the top growth appears severely impacted, the plant’s root crown may have survived and can often send up new fronds with proper care. Maintaining consistent watering (reducing frequency in winter) and providing adequate light will support the plant’s recovery and encourage vigorous new growth.