From my perspective as a spider plant (Chlorophytum comosum), I must start by explaining my origins. I am not a native to the varied climates of the United States. I hail from the subtropical and southern regions of Africa, where the environment is consistently warm, humid, and without the threat of frost. My fundamental genetic programming is built for these conditions. I thrive in temperatures between 55°F and 80°F (13°C - 27°C). This means I am, by nature, a tender perennial. My leaves and root system have no natural defense against freezing temperatures; ice crystals form within my cells, causing irreparable damage that leads to wilting, browning, and ultimately, my demise.
Humans use the USDA Plant Hardiness Zone Map to categorize geographic regions based on their average annual minimum winter temperature. This is an incredibly useful tool for determining if a plant like me can survive the winter outdoors year-round. The zones range from the coldest (Zone 1) to the warmest (Zone 13). For me to even consider permanent outdoor living, I require a location where the winter lows never dip below freezing. This typically corresponds to USDA Hardiness Zones 9 through 11. In these zones, which include parts of Florida, southern Texas, and coastal California, the winter temperatures generally stay above 20°F to 30°F (-7°C to -1°C), allowing me to persist as an evergreen perennial in a sheltered spot.
For the vast majority of the US, which falls outside my narrow hardiness range, I can still enjoy an outdoor lifestyle, but it is strictly a seasonal vacation. Once the danger of spring frost has passed and nighttime temperatures are consistently above 50°F (10°C), I absolutely love being moved outside. A spot with bright, indirect light or dappled shade is perfect for me; direct afternoon sun can scorch my leaves, causing unsightly brown tips. The increased air circulation, rainfall, and humidity often trigger a growth spurt, and I may produce more of my characteristic "pups" or spiderettes on long, hanging stolons. This period of outdoor living is highly beneficial for my overall vigor.
As the summer wanes and autumn begins, my human caretaker must be vigilant. The single most important event of my year is the move back indoors before the first fall frost. Even a light frost is a lethal event for me. The move should be done gradually, perhaps by first placing me in a shadier location for a week to acclimatize, to reduce shock. It is also crucial that I be inspected for hitchhiking pests like aphids or spider mites who may have found me an agreeable host over the summer. A gentle spray of water or an application of insecticidal soap ensures I don't bring any problems inside to other houseplants.
