Should I Use Incandescent or Fluorescent Indoor Grow lights for Plants?

Let’s address the most frequently asked questions in the field of indoor garden lighting.

Should I use “Incandescent” or “Fluorescent” lights?

The color of fluorescent lights match the color of day light. The bluish tint of fluorescence is closer to the light available in the day time while the red-yellowish tint of an incandescent light is not quite in tune with this spectrum.

Incandescent lights

Incandescent plant grow lights are not true plant growing lights, they are best utilized for spot lighting some plant grouping or a specific plant. They also burn hot and tend to scorch a plant placed too close to it. You should always maintain a gap of at least 24 inches between the plant and the incandescent light source.

Fluorescent lights

These are of course the best choice as plant grow lights, there are two varieties available – Standard and High output. You can use the standard lights for starting seedlings and for small plant beds meant for transplanting(for early spring). They are quite suitable for growing lettuce, herbs and other leafy vegetables year around.

High output lights are twice as bright as the standard ones while having a thinner profile and using the same input electricity.
They provide a cooler light and are well suited for lighting beds of plants growing up to 36 inches in height.

Compact fluorescent lights can be used to focus light upon large plants.

HID fluorescents can be used for indoor bed of plants that require plenty of natural sunlight. Metal halide HID lights are as close as you can get to natural sunlight, their whitish rays have a CRI index close to daylight. In fact plants growing under metal halide HID lights resemble their outdoor growing counterparts closely. These are a definite choice if you want to grow plants indoors till maturity.

High pressure sodium HID lights are sometimes used to exploit their ability to expedite the flowering and fruiting cycles of the plant due to its reddish-orange tint. But these lights are not optimal growing lights and most plant don’t thrive well under these sources. They are mostly used to supplement the outdoor lights in certain greenhouses.

What about LED grow lighting?

This is a relatively new technology which is still in an experimental phase but the results are not very promising. Most farmers who tried the LED grow lights have verified that the results are far from encouraging. Moreover the cost of a half decent led grow lighting structure is close to $2000! For now it is safe to assume that conventional indoor garden lighting is here to stay.

Who makes the best grow lights?

Presently Agrosun is a brand that provides competitive products and pricing for a whole range of indoor garden lights starting from standard fluorescents to HID lights. You can check out their products at

When to use water cooled grow lights?

If you live in a region where the room temperature is usually quite hot, then your tubes and bulbs will have minimum cooling and will tend to emit a lot of heat. In such regions it is better to use water cooled grow lights rather than depend upon the normal air cooled ones, especially while using plant stands. In fact the water cooled lights emit less heat and thus keep the room temperature from getting too hot especially in dry climatic regions.

These lights have special fixtures that circulate water for the cooling effect. You can look into Fresca Sol Water-cooled lights if you are interested in buying one.