Indoor Plant Investigation - 3
WAVELINKS 200 photonic engine 4 bar Lighting System
July 28, 2015 8:46 PM
Purpose is to see how the distance from the light source affects the growth of plants. In this case I am growing grass, because of its speed to germinate and grow. This is a continuation of my investigation for a greater purpose or growing plants indoors to create a continuous supply of fresh greens and what not for salads. See previous investigation -1 and investigation - 2 results, summary, and conclusions on which this investigation is based.
Variables: the distance of the top of the soil from the light source: 4 inches, 8 inches, and 12 inches. All three pots are the same size, with the same kinds of soil mixed together before filling each pot, sowed two teaspoons of tall fescue grass seed in each (selected by having some on hand), directly below the four wave light system, watered with the same amount of water put in each container.
Selected light source based on the requirements of low power usage (25 watts), reduced heat resulting in the use of less water, focused wavelengths with light specific for the needs of plants, and being able to control different light frequencies during the illumination period.
For information about the choice of a light source for the investigation check out these sites:
Light and Timer information
Placement of bars from the outside of one side to the outside on the other side to make a 4 wave mix::
- LK2G2 6000k 1814 Versa bar
- VXLR Deep Red 2214
- LK2 Blue 0613
- QCWL 2500k 4113 Versa bar
Light strips that turn on at 7 AM and off at 9:30 PM for a total 14 and one-half hours of light.
Two teaspoons of grass seed was sprinkled across the top of the soil in each container. Then, the soil was raked and seed was raked to a quarter inch depth to distribute and bury some of the seeds.
Four cups of water was used to bottom water the three containers. When the water was absorbed the containers were moved to their various positions from the light source and 10 teaspoons of water was sprinkled on the soil of each container.
Day one - five
Top picture shows the set-up. The lights are a couple of inches above the bottom of the light fixture and the soil is below and at an angle to the ruler. The distance is 4 inches, 8 inches and 12 inches.
This picture shows what the container looked like for the first five days.
On day six I was traveling and didn't get pictures taken. As it would happen on day 7 when I returned grass was growing. Added 10 teaspoons of water to the top of each container.
Click here on on image below to view video...
Day 9 morning
Day 9 night
On day ten I moved all three to the bottom level and took two pictures of all three:
Moved all the plants down so that the canopy of the grass was 4, 8, & 12 inches from the light source as when the investigation began.
The results indicate the distance from the light source to the surface of the dirt or grass crown height of 4 inches, 8 inches, or 12 inches made no significant difference. All three were pretty much the same. The height of grass growth and the quality of the growth is for all intense purposes the same. The intensity of light does not diminishes significantly for the distance of four - twelve inches at least.
It would be interesting to conduct additional investigations that would seek to establish limits. Maybe next time investigate 12,24, & 36...