February 16, 2022

Grow Factors: Light Window

Grow Factors: Light Window

Ladies and Gentlemen, this is the first in a series of posts to describe the intrinsic benefit of controlling all aspects of a 'grow'. There are many fascinating characteristics of plants that are an expressed response to their natural environment. This series will explore important characteristics that are under the control of a sophisticated controlled-environment user. Once you understand how plants evolve in their environments, you can infer how to manipulate them beneficially in an artificial habitat.

When I say light window I refer to day length simulated in an artificial environment. Naturally, the Earth - Sun gravity covenant turns the day length and seasons by angling the tilt of our axis toward and away from the golden glowing hearth as all the whole system spins in perfect balance. At the proximal and distal tilts the day length is its most extreme, influencing climate with light and darkness. Near these maxima and minima, the day length is relatively stagnant. In the balanced equinoxes, the tilt is perpendicular to the radial light of the sun causing daylength to be the same at opposite times of the year. Although the day length is equal in the Spring and Fall, the rate of day length change is its highest.

When the day length is changing at high speeds, plants are built to respond in dramatic ways. For certain plants and ecosystems, this change begets Spring and it's time to turn on the charm for some pollinators. For others, it's an occasion to ripen fruit for progeny and get rid of leaves since the operating cost is too high for no reward in the dark winter months. With this in mind, consider how plants differentiate themselves at different latitudes.

At higher latitudes, the equinox transition is more dramatic and plants are more specialized to survive in drastically dissimilar conditions between Summer and Winter. Plants near the equator have an unchanging plethora of light all year and are more focused on full-filling or creating their niche in the ecosystem. This is part of why there is so much plant diversity at the equator in tropical environments and more established characters at northern and southern latitudes.

Now that we've covered how day length / light window interacts with plants, let's consider how we can use this innate response in a controlled environment to our advantage. Some plants are more sensitive to this window than others. Vertical farms usually grow lettuce under non-stop light because the lettuce plant doesn't really need night to do its thing. Other plants that have flowering mechanisms rely on day length and light window to coordinate their blossoming with the most advantageous part of the year. This is why farmers follow the same timeline every year. Controlled environment users can seemingly manipulate the orbit of Earth around the sun and bend the seasons. If you have a flowering plant, you can trick it into fruiting whenever you want by manipulating the light window. This can be used to grow a plant to a larger or smaller size than it normally would in natural light before producing its crop.

How a plant is designed to respond to day length reveals where it spent time evolving in the distant past. Pre-historic humans domesticated plant species and transporting them across the world leaving an evolutionary mark that can be observed in their epigenomic expression to environmental conditions. Therefore, the mysteries of the plant kingdom are intertwined with humanity's ancient history. Light window / Day length response is one of these expressions that when examined further can reveal multitudes about a species, including it's path of origin. It is my hope that with a collective network of controlled-environment grow users all pushing the limits of controlled environmental response we can unlock the secrets of humanity's past as well as illuminate grow techniques of the future.