Indoor Growlight 15W

All forms of life in our planet are governed by an inner Circadian Clock. The plant circadian clock regulates daily and seasonal rhythms of key biological processes, from growth and development to metabolism and physiology.

How does a plant day looks like using growlights? A plant day is triggered by 'seeing' the sun rise as short-red light and ends at sun set as far-red light. In the full spectrum lamp, the short-red light accounts for 35.5%; the far-red light 5.5%; the blue light 22% and the green light 37% of the light emmited. Every type of light play a role in the process of growth.

Blue Light Spectrum (400–499 nm)

• Blue light drives peak chlorophyll absorption which is needed for photosynthesis, healthy root development and structure (increased density, such a thicker stems, wider trunks, wider leaves). It's essential for seedlings and young plants during early vegetative stages. Blue light suppresses extension growth (leggy plants) making them shorter and have smaller, thicker and darker green leaves.

Green Light Spectrum (500–599 nm)

• In Nature, green light may better penetrate a canopy than other colors on the visible spectrum, and because plants use less green light than others (because they are green), it travels lower into the forest floor allowing smaller plants to get some rays too. Although green light is the is widely considered the least useful light it still plays a small role in regulating photosynthetic pigments, water absorption, stomatal formation, stem and leaf growth. It's essential transplanted plants after germination.

Short-Red Light Spectrum (600–699 nm)

• Short-red light is the first light a plant 'sees' as it wakes up. Red light is the most effective light spectrum to encourage photosynthesis as it’s highly absorbed by chlorophyll pigments. Red light wavelengths encourage all vegetative growth and is when most energy will be produced for the plant's metabolism.
• At around 660nm a plant senses bright sunlight exposure.  From 730nm, a plant will detect light “shade” from another plant or leaves higher up the canopy, so stretching of stems and leaves occurs.

Far-Red Light Spectrum (700–850 nm)

• The Far-Red light is the last light a plant 'see', just before going to bed. It is how a plant knows the day is ending and a new one will follow triggers the awareness of the seasons culminating in flowering and fruit production. The plant counts da intervals between the short-red and far-red lights. Longer intervals means winter times, shorter intervals means spring and summer. Far-red light regulates plant morphology and photosynthetic capacity. Far-red light can also influence leaf angle and increase plant height, leaf area and density - they become bigger/winder/longer to capture more light energy.

First of all, light intensity is measured in LUX lux via an electronic device called a luxmeter. Every plant has a minimum and a maximum light absorption capacity required to survive, grow and produce (flowers and fruits).

Different parts of our home will receive different intensity and quality of light throughout the days and seasons. Plants perceive light different from us. A room might be very bright for us, but for a plant it is considered shaded. It is important to know where to place your plants so that they get the light they need.

• Room with many windows: 400 a 800 lux
• North-facing window: 500 a 2500 lux
• South-facing window: 10.000 a 20.000 lux
• East-facing window: 2.500 a 10.000 lux
• West-facing window: 2.500 a 10.000 lux

Think os light as the energy that will fuel the plants engine to wake up, breath, grow and produce. The higher the light intensity, the more energy available, however, plants have a minimum and a maximum light absorbing capacity. Too light will shut down the engine, too much light will saturate and kill the engine as well. Balance is everything.  But, how much light (lux) does a plant really need? We find the answers by observing that plant in its natural habitat and surrounding climate. 

• Direct bright light = full sun exposure (outdoor) or the sunniest spot (indoor): between 20.000 and 50.000 lux (8 to 12 hours of light)
• Indirect bright light = obstructed sun light (outdoor) or indirect sun / sunniest spot (indoor): between 10.000 and 20.000 lux (6 to 8 hours of light)
• Medium light = partially shaded (outdoor) or a few meters away from the brightest South-facing window (indoor): between 2.500 and 10.000 lux  (4 to 6 hours of light)
• Low light = shaded by building or bigger trees (outdoor) or next to a North, East or West facing window (indoor): between 500 and 2500 lux (2 to 4 hours of light).

Some plants require more sun exposure because they need more energy to survive. Example: To keep a cactus alive 20.000 and 50.000 lux is needed everyday between 8 to 12 hours of light exposure. A cactus is most happy in a summer day than in winter. That explains why we have sad cacti and succulents back home. They are unhappy and depressed!

Most sun loving plants will require 10.000 to 50.000 lux to be happy, meaning 10.000 lux is the minimum and 50.000 is the maximum. If they get >60.000 lux exposure for a long time they will start getting scorched. If they get <10.000 lux they will start to develop stunt growth, diseases and be susceptible to insect attacks.

Most indoor plants are from tropical and sub-tropical rain forests where they are sheltered by big tall trees. They let through very little direct sunlight but mostly green light. This is the environment we try to replicate at home via grow-lights. It is just enough to trick them into thinking it is a sunny day above the canopy, but I only get a fraction of those rays through. 500 lux is the bare minimum a plant needs in order to complete its biological and metabolical processes. Anything above 2.500 lux will most certainly have negative effects and kill your plant of too much light exposure.

Once introducing any grow-light to your plant, it is important to follow its light needs looking at nature.

Switch the light on together with your current sun rise schedule. Switch off with your sun set hours.

The same grow-light can supply different types of plants as long as they are in a composition or closely together.

Plants that require more light should be closer to the light source, or higher up in the composition. Bigger and taller plants will obstruct medium and smaller plants from getting this light.

When using the 15 watts (1350lumens) Sansi Grow-light please follow the advised distances from a plant (or composition):

• 20cm (maximum distance): it will give 2350lux
• 30cm (advised distance): it will give 1150lux
• 60cm (minimum distance): it will give 290lux
• 90cm (not advised): it will give 130lux
• 100cm (not advised): it will give 100lux
• 120cm (not advised): it will give 80lux
• 150cm (irrelevant): it will give <50lux

If you need more light coverage, add a second grow-light in the opposite side or from above. The Santi grow-light bulb offers flexibility to play with your favourite lamp shades in your home as long as it has an E27 fitting.