How High Should Your Grow Lights Be Above Your Plants?


So you have everything you need to start growing those beautiful plants in your indoor garden. You’ve got the plants, the appropriate nutrients, and the lights. So you are well prepared for the planting process. But, before you hit the light switch on, are you certain that the lights are hanging right and within a proper distance from your plants?

Hanging the lights way too low will burn and stunt your plants. Hanging them way too high, will leave your plants weak and unhealthy. Determining the proper height distance depends on the type of lights you intend to use. Some lights have to be hanged a bit far from the plants so that the plants don’t get burned. Others need to hang low enough to provide the amount of light needed by the plants for proper growth.

To ensure optimized light conditions for growth, you need to hang your lights at a proper distance such that your plants are safe from burning, but are still getting enough light.

So let’s talk about the different types of grow lights you can use to hang in your indoor garden.

High-Density Discharge Lights

Some people are still using HID grow lights, those produce a great deal of heat, so they cannot be hanged close to plants. Otherwise, the plants will burn and die. On the other hand, hanging them too far away will cause the plants to become weak they are not getting enough light. The ideal height distance between the plants and the lights should be at least 12 inch (30 cm). Also, the more intense the light, the further away the lights have to be from the plants.

Let´s take two practical examples:

  • For instance, if you are using 1000watt HID grow lights, hang them a least 15 inch (38 cm) away from the plants. Depending on the intensity of the light, you will not want to hang the lights higher than 30 inch (76 cm) above the plants.
  • If you are using 400 watt HID grow lights, then hang them at a distance of 30cm away from your plants. If you are using 600 watt HID grow lights, hang the lights about 14 inch (35 cm) away from the plants.

Since HID lights emit quite a lot of heat, the distance between the plants and the lights should not be too close. Much better and energy efficient alternative is to use LED lights instead of HID.

LED Grow Lights

Much like HID, LED grow lights emit enough light that if hung close to plants, the plants will get burned. But, with LED grow lights, it’s not the amount of heat they generate that you should be worried about, it is the light temperature.

While HID’s emits plenty of good light temperatures, LED’s produce more light than HIDs and even the sun. Therefore, if those rae too close to plants, they will cause light bleaching, which is bad for the plants much like over-heating.

Let’s take two practical examples:

In short, LEDs do not produce too much heat, but you still need to hang them at a good height distance from the plants.

Fluorescent grow lights

Fluorescent grow lights produce a good amount of heat and light, but not as much as HID’s or LED’S. While the lighting they produce is sufficient for plant growth, they need to be hang pretty close to the plants.

The only issue that comes with using fluorescent grow lights is the kind you intend to use because they are not all similar. Some are capable of generating enough heat over a period of time because of their small size, whereas there are longer ones that do not generate much heat because they can dissipate. Furthermore, the more bulbs you will use, the more heat they will produce, the further away you need to hang the lights from the plants.

Induction lighting

Induction lighting is a fairly new technology that uses radio or microwave frequencies to generate light. Essentially, the technology uses a sealed bulb design and unlike standard fluorescents and HID’s, it relies on electrodes to generate electricity.

Induction lighting does not produce a lot of heat and light; therefore, they need to be place close to the plants.

Two types of induction lighting are used in indoor gardening:

  1. Induction fluorescents

Induction fluorescents have many of the advantages that standard fluorescents, but unlike their counterparts, they do not degrade quickly. The set up cost of these fixtures is relatively high; however, you will never need to worry about bulb replacement throughout the fixture’s entire life-span.

  1. Sulfur Plasma

Sulfur plasma inducting lighting technology is quite new in the market and not many people are using it. Mainly because the lighting system is very expensive to set up and this is why. Although sulfur plasma emits as much light as HID’s, it has one great advantage, the spectral light it produces is close to that of the sun’s making it suitable for plant growth.

Final Thoughts

Before purchasing an indoor gardening lighting system, gather as much information as you can on the different types that are available in the market. All the aforementioned grow lights can help grow plants. But, some are more efficient than others and some are more costly than others.

In the end, it depends on the size of your indoor garden and your budget. But, keep in mind that some of these grow lights like the induction lighting lights may cost an arm and a leg to set up, but once that is done, you will not incur any further costs for years to come. On the other hand, induction lighting does not generate much heat.

If you are new at indoor gardening, you may be enticed to try out the much newer indoor lighting technologies, which is fine. But, you could end up getting disappointed when you realize that you need to get other grow lights to work together with newer ones to produce sufficient light for plant growth.

Watch video about “How Far Should My Growlight Be From My Plants?”

Our recommendation is to choose always LED based grow lights as those are energy efficient, and do not generate too much heat while especially full spectrum models offer all required wave lengths for the perfect growing conditions. Furthermore, those are quite reasonably priced and there are models available for every need.

Leave a Reply

Your email address will not be published. Required fields are marked *