Lighting, plants seem leggy

A question from a fellow grower:

I downloaded the book to help me grow my own but I have a problem with the lighting for the plants I have one light cfl 1150 lumens but it seem that only one of the plants is growing nicely … the other two is developing legginess they are about 3days younger but about 2.5cm taller and the box is small they 2 weeks old now

they are spaced 5cm from each other because they are still young will plant them into a bigger pot later

please advise if possible

If I understand correctly you only have the 1 light correct? What is the distance from the bulb to the top of the plants? Are the ones stretching not directly under the light?
The majority of times you run into legginess (called “stretching”) it is due to the light being to far above the plants. This causes them to stretch to the light in order to get more of those lumens for photosynthesis.

add another light or 2 as J said they are stretching to get closer to the light and moving them closer or adding more light will help

Size of your grow room ? have a formula that determines the correct amount of lumens needed per square foot of grow space

Good day Guy’s

sorry I took so long to reply we had a major power outage here in South Africa
My light is about 10cm (4inch) above the plants. and my grow box in not that big it is 800mm x 800mm.i only grow for personal use so the grow room will be to big.Thank you for taking the time to read my request for help it is something that we do not have a lot of here.

Yes…J the one’s that are stretching is not directly under the light but with should be fine because like I said my grow box is small so I thought that one light should be sufficient be box is also lined with foil so that the rays can better be received from all sides.

800mmx800mm and you will need about 400-500 watts. This is the amount the lights use in actual electricity.

The standard is about 40-50 watts per square foot or about 500 watts per square meter minimum, regardless of the type of lights you use.

Happy growing,


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