Chilis light - duration and light colours
Chilli plants really blossom with 14 - 16 hours of daylight. From May to October, chillies get enough sun in a bright garden and on a south-facing balcony. However, hot chilli varieties need much longer to germinate, grow, form flowers and finally ripen fruits.
With most Capsicum species, you should start growing early. As the sunlight from January to April is often barely sufficient for chilli seedlings, you can support their growth with artificial plant light.
You can tell if your plants need additional artificial light by their pale green and spindly growth. Even though chillies are dark germinators, i.e. they do not need light for germination, it is best to provide sufficient light from the beginning.
A growing station can be inexpensively equipped with a timer, light strip and fluorescent tubes. During the growth phase, fluorescent lamps in the colour 865 Daylight are optimal. When installing the lamps, make sure they are a short distance from the tips of the plants. No more than 60 cm, otherwise too much light will be lost. At less than 15 cm, you may find that their chilli leaves get too warm.
If you grow your chillies indoors all year round, it makes sense to change the light spectrum at flowering time. Neutral white in light colour 840 supports fruiting with a slightly higher red component.
White light is composed of the rainbow colours: red, orange, yellow, green, blue and violet. Green plants absorb for the most part only the red and blue spectrum for photosynthesis. The green spectrum plays almost no role.
Imagine the light on a clear day in winter and late summer. Can you remember which colour of light was predominant in each case? In winter it was a rather bluish colour, in late summer it was more reddish.
Plants also notice this colour difference. With a blue spectrum you promote the growth of chillies, red light promotes bushy growth, blossoms and fruiting.
LED plant lights
LED plant lights are usually composed of many small diodes. A mixture with a ratio of two blue and one red diode can be seen quite often. The advantage of LED's is low heat generation, high light yield and thus more energy efficient than fluorescent lamps. The disadvantage is the higher purchase price.
High Power LEDs are available individually in 1 and 3 Watt. The wavelength is perfectly adapted to the needs of chillies.