For us Impatiens, maintaining an appropriate temperature is not merely about comfort; it is a fundamental requirement for metabolic processes, growth, and ultimately, survival. Our ideal temperature range is between 65°F and 75°F (18°C - 24°C) during the daytime. This range provides the optimal thermal energy for photosynthesis to proceed efficiently, allowing us to convert light into the sugars that fuel our growth and produce our vibrant blooms. Temperatures consistently above 80°F (27°C) can cause us significant stress, leading to bud and flower drop as we attempt to conserve energy and moisture. Conversely, we are extremely sensitive to cold. Exposure to temperatures below 50°F (10°C) will cause chilling injury, manifesting as wilting, blackened foliage, and a complete halt in growth. A frost is fatal. Therefore, a stable, warm environment is key to our prosperity indoors.
Our relationship with humidity is deeply tied to our physiology. Our succulent stems and tender leaves have a high surface area from which water can readily evaporate, a process known as transpiration. In our natural, often humid habitats, the moisture in the air slows this water loss. To thrive indoors, we require a relative humidity level of at least 50% or higher. When the air becomes too dry, especially in homes with heating or air conditioning, our rate of transpiration exceeds our roots' ability to draw up water. This imbalance results in tell-tale signs of distress: leaf edges and tips turning brown and crispy, overall wilting, and flower buds dropping before they have a chance to open. Maintaining adequate humidity is crucial for keeping our tissues turgid and our physiological processes functioning smoothly.
These two factors do not act in isolation; they are intrinsically linked. Warmer air has a greater capacity to hold water vapor, meaning that at a higher temperature, the same absolute amount of moisture translates to a lower relative humidity. For example, air at 75°F with 50% humidity holds more water than air at 65°F with 50% humidity. This is why a warm, dry room is particularly challenging for us. You must consider both metrics together. The ideal scenario is a stable, warm temperature paired with consistently moderate to high humidity. This combination minimizes our water stress, supports robust photosynthesis, and encourages the prolific blooming we are known for.
We will clearly communicate when our environment is not ideal. Be observant for our signals. Wilting, brown leaf tips, and dropped buds are our primary cries for help due to low humidity and/or high heat. Yellowing leaves that feel soft and mushy may indicate cold damage or overwatering in a cool, poorly ventilated space. To create a perfect microclimate for us, consider grouping several plants together to create a communal humid zone through collective transpiration. Placing our pot on a pebble tray filled with water (ensuring the pot sits above the waterline) is an excellent way to boost local humidity through evaporation. For severe cases, a small room humidifier provides the most consistent and effective relief, directly addressing our need for moisture in the air.
