From my perspective as an Echeveria, sunlight isn't just energy; it's a specific recipe. In my native high-altitude habitats, I am bathed in intense, full-spectrum light. Your standard indoor room light is a bland, unsatisfying meal to me. I crave the specific blue and red wavelengths found in the solar spectrum. Blue light keeps my growth compact and sturdy, encouraging the vibrant colors you admire. Red light, while less critical for my shape, supports my flowering cycle. Therefore, the grow light you choose must provide this full, balanced spectrum, often labeled as "full-spectrum" or "daylight," to truly mimic my ideal conditions and keep me from becoming pale and stretched out.
How strong the light is and for how long it shines are crucial. I am a sun worshipper. A weak light placed too far away is like a perpetual cloudy day; I will etiolate, stretching my stem and spacing my leaves to desperately find more. To thrive, I need high-intensity light. For most LED panels, this means placing me only 6 to 12 inches away from the source. As for duration, I require a long, consistent "day." A photoperiod of 12 to 14 hours is perfect. Please use a timer; it provides the consistency I need for my internal clock (photoperiodism) and prevents you from forgetting. This long exposure to intense light is also what triggers the production of my best pinks, reds, and purples.
I will communicate clearly whether the light setup is working. Observe my leaves closely, as they are my primary language. If I am receiving ideal light, my rosette will remain tight and compact. My stem will be short and thick, and my leaf coloration will be deep and intense. If the light is too weak or too far, you will see me etiolate: my center will pale, and I will stretch awkwardly towards the light source. Conversely, if the light is suddenly too intense or too close, I may show signs of stress akin to sunburn. This can manifest as bleaching (losing all color), or reddish-brown scorch marks on the uppermost leaves. This is my plea for a slight adjustment in distance.
Brighter light fundamentally changes my metabolism. Under powerful grow lights, I will photosynthesize more efficiently and use water much more quickly. This means you must adjust your watering habits; my soil will dry out faster. However, the principle remains: always wait until I am completely dry before watering me again. Furthermore, good airflow around my leaves is vital to prevent moisture from settling and causing rot, especially since I am now indoors. Finally, just like in nature, I appreciate a period of rest. While you can use grow lights year-round, providing me with slightly shorter "days" (e.g., 10 hours) during the winter months allows me to enter a dormant phase, which is healthy for my long-term cycle.
