Have you ever wondered why your plants don’t thrive under artificial light as they do in the sun? The key lies not simply in the brightness, but in the light recipe. For plants, light is not just energy, but also an information signal. In this guide, you will learn how to revolutionize your harvest with precise light recipes.
What is a light recipe for indoor growing?
Forget the simple “on-off” principle. A light recipe for plants is a precise timetable for your grow LEDs or other lighting. It defines the exact mix of light colors (spectrum), the intensity and the daily light duration (photoperiod) – tailored to the specific plant species and its current growth phase. It is the blueprint for perfect photosynthesis.
The science behind light: photosynthesis & photomorphogenesis
Plants “see” light very differently from us. They use different pigments to react to light:
- Chlorophyll A & B: Absorb mainly red and blue light for photosynthesis. Blue light promotes compact, vigorous growth (veg phase). Red light stimulates the stretch phase and flower formation.
- Phytochromes: These pigments perceive red and far-red light. They control germination, the branching of the plant and the time of flowering. The ratio of red to far-red is crucial here.
- Cryptochromes: React to blue and UV light and influence the circadian rhythms of the plant.
A light recipe specifically manipulates these processes to steer growth in the desired direction.
The ingredients of your light recipe: spectrum, duration & intensity
Your light recipe is made up of three main ingredients:
- Light spectrum (color composition):
- Blue-heavy (450-500 nm): Ideal for the vegetative phase. Promotes dense, bushy leaf formation.
- Red-heavy (620-680 nm): Essential for the flowering phase. Promotes stretch, flower set and fruit formation.
- Full spectrum (white LEDs): Imitates the sun and is often a good all-round solution.
- Light intensity (PPFD):
- Is measured in PPFD (Photosynthetic Photon Flux Density). It indicates how many photosynthesis-driving photons hit a leaf. Too little PPFD = slow growth. Too much PPFD = light burn (bleaching of the leaves).
- Light duration (photoperiod):
- How many hours of light does the plant get per day? Short-day plants (e.g. cannabis) need 12 hours of light/12 hours of darkness to flower. Long-day plants (e.g. lettuce) need longer periods of light.
Examples of simple lighting recipes
- Lettuce (Veg phase): 18 hours of light, 6 hours of darkness. Cool-white or blue-heavy spectrum. Medium PPFD.
- Basil (continuous): 16-18 hours of light. Full spectrum. High PPFD for lush leaf growth.
- Strawberry (flower/fruit): 12-14 hours of light. Red-heavy spectrum. Very high PPFD for sweet fruits.
- Cannabis (vegetative phase): 18 hours of light, 6 hours of darkness. Blue-heavy or full spectrum. Medium to high PPFD for vigorous, bushy growth.
Cannabis (flowering phase): 12 hours of light, 12 hours of darkness. Red-heavy spectrum. Very high PPFD for dense, resinous buds.
Explanation for the addition:
Cannabis is a photoperiodic plant, which means that the duration of light (photoperiod) flips the crucial switch for flowering. This makes it a perfect example to demonstrate the effect of light recipes. The division into two clear phases shows how light can be used not only to promote growth, but also to control the entire life cycle of the plant. The specific mention of bud quality (“resinous”) speaks directly to the main goal of many growers and emphasizes the practical benefits.
Why precise lighting recipes are worthwhile
It’s not just about faster growth. You can achieve this with the right plant lighting:
- Higher yields: More leaf mass, more fruit, more flowers.
- Better quality: Increased sugar and nutrient content in fruits and leaves.
- Controlled morphology: more compact plants that require less space.
- Energy efficiency: You don’t waste electricity on light that the plant cannot utilize optimally.
Conclusion: Become a light cook for your plants
Indoor growing without a plan is like cooking without a recipe – it will be edible, but not great. A well-thought-out lighting recipe makes you a master gardener who understands the biology of your plants and directs them in a targeted manner. Invest in a dimmable LED with a variable spectrum and experiment. Your plants will thank you with lush growth!
Manage your personal light recipe library with the Smart Grow app – from perfectly pre-configured spectra to individual masterpieces designed for your cannabis strains and cultivation strategies. Whether 2.5-3 g/W harvest or aromatic flowers – with this technology you are always one step ahead.
While many systems work with rigid programs, our technology gives you the freedom to design your own lighting recipe – an advantage that others cannot offer.
