How far should LED grow lights be from plants?
When it comes to growing plants indoors, the correct placement of LED grow lights is critical.
If your lights are too close to your plants, they could cause damage to them through heat or over-stimulation.
However, if the lights are too far away then you may not maximise photosynthesis with sufficient light intensity.
Here is what you need to know on correct light placement, for everything from seedlings to larger plants.
Correct LED grow light positioning
Where your lights should be placed in relation to your plants depends on the type of plant, the plant’s growth stage and the intensity of the grow lights.
However, the following ranges can be used as a general guide.
- Seedlings Stage: 60-90cm
Delicate seedlings can become stressed by too much light intensity or too much heat generated by the lights. Start the lights further back and then gradually reduce the distance as the seedlings grow.
- Vegetative Stage: 45-60cm
During this stage of a plant’s development, they require more light for photosynthesis and rapid growth. Therefore, grow lights should be moved closer above the canopy.
- Flowering/Blooming Stage: 30-45cm
This is the stage when plants require the highest levels of light intensity to develop flowers and lights should be placed closest to the top of the canopy. However, make sure not to place high-intensity lights too close, because that can cause damage and stunted growth.
The intensity of the lights matters a lot when it comes to these recommended distance ranges.
For example, high-intensity 1000W light systems should be placed at the very upper ends of these ranges to help avoid light burn.
Lower-intensity 200W light systems are suitable for placement at the closest points of these ranges, without causing harm.
If you purchase new LED grow lights, be sure to carefully read any manufacturer recommendations on how best to place them above your plants.
Monitor your plants for signs of over-exposure
Most plants will show visible signs of stress if grow lights are placed too close to them, which are important to look out for.
These signs of stress can result from excessive light intensity or the heat generated from grow lights.
Signs that your lights are too close and may need to be moved further away from the plant canopy include:
- Leaf Burn: Where brown or crispy spots arise, particularly at the ends or on the edges of leaves.
- Yellowing Leaves: When leaves lose their vibrant colour and become paler, it is often a sign of stress.
- Stunted Growth: Plants exposed to too much light can display much slower growth.
- Wilting: In extreme cases, excessive light can cause plants to wilt, even with sufficient watering.
All your indoor growing needs in one place
At A-Grade Hydroponics, we are experts in indoor plant growing and can help you assemble the perfect set up.
We stock a wide range of quality LED grow lights, including dimmable options and systems which can be controlled by mobile phone apps.
Check out our online store, come visit us at our Melbourne shop or give us a call on (03) 9555 6667 if you want to learn more.
