Fluorescent Light And Plants: Lighting Options For Indoor Gardening

Indoor Potted Plants Under Fluorescent Light
fluorescent light plants
(Image credit: Brandon Blinkenberg)

The right kind of grow lights can make all the difference in how your plants perform. Using fluorescent garden lights to enhance plant growth allows you to grow a host of plants in an interior space. Standard indoor lights do little to influence photosynthesis, while using fluorescent lighting placed closely to the top of the plants can help drive this important plant process.

About Fluorescent Light and Plants

Modern plant lighting has focused on the LED sources of light, but fluorescent lights are still widely available and easy to use. They are an excellent source of light for young seedlings and plant starts. Fluorescent lights don't last as long as LEDs but are easy to find and install. Whether you use them vs. LEDs depends upon the light requirements indoors that your particular crop or plant needs. Fluorescent lights were once the "go to" source of plant lamps. They fell out of favor because they don't last very long, are delicate, bulky, and don't provide a high lumen intensity. Therefore, the bulbs are not ideal for fruiting and flowering plants. Modern fluorescents, however, have increased the lumen output, come in compact bulbs and last longer than their predecessors. In fact, new T5 lighting systems produce less heat than the old bulbs and can be placed closer to the plant without worrying about burning foliage. They are also more energy efficient and the light produced is readily used by the plant.

Determining Lighting Requirements Indoors

A good light meter can help you determine how bright you need to make the light system. Light for growing plants is measured in foot candles. This measurement indicates the amount of light given off a foot (.30 m.) away. Every plant needs a different amount of foot candles. Medium light plants, such as tropical rainforest specimens, need around 250-1,000 foot candles (2500-10,000 lux), while high light plants need over 1,000 foot candles (10,000 lux). You can increase the amount of light a plant receives even with a low output bulb by using a reflector. These can be purchased or use aluminum foil to focus light.

Fluorescent Lighting Options for Indoor Gardening

If you are considering using fluorescent lighting, there are a couple of systems to consider.

  • The new T5 fluorescent garden lights are tube lights which provide light on the blue spectrum and are cool enough to touch safely and won't burn young plants. The number 5 refers to the diameter of the tube.
  • There are also T8 tubes that are similarly efficient. Both produce plenty of light but are of a lower wattage than older fluorescents and, therefore, more economical to operate. Purchase tube lights with an HO rating, which indicates high output.
  • Next are the CFLs or compact fluorescent tubes. These are great for small grow spaces and can be used in an ordinary incandescent light fixture.

No matter which you choose, fluorescent light and plants will increase growth and output in interior situations.

Bonnie L. Grant

Bonnie Grant is a professional landscaper with a Certification in Urban Gardening. She has been gardening and writing for 15 years. A former professional chef, she has a passion for edible landscaping.