How much light do your plants need when using grow lights?

How much light do your plants need when using grow lights?

The amount of light your plants need largely depends on the type of plant and the location of the plant within your living arrangement.

For example, once sprouted, most vegetable seedlings and other garden plants require at least 12 hours of good light per day, along with 8 hours of darkness. However, they'll grow the best with around 16 to 18 hours of light. Houseplants are happy with less, where 6 to 12 of light is sufficient (depending on the type of plant).

What is the right duration when using grow lights?

No matter what types of plants you are growing, you must give them a rest. When it's dark, plants respirate, which is an important part of their growth process. The balance of rest time to active growth time affects many biological processes, including the growth rate, and the setting of buds and fruit. A grow light with a built in timer makes it easy to get the duration right. All our grow lights have built in timer that automatically turn on and off when set up.

There are three categories relating to their preferred day length: short-day, long-day or day-neutral.

Short-day plants, such as chrysanthemums, kalanchoe, azaleas and begonias, will thrive on less than 12 hours of light per day. In fact, these plants must usually go through a series of even shorter days before they will set buds and flower.

Long-day plants require 14 to 18 hours of light each day. Most seedlings for vegetables and garden flowers and succulents are long-day plants. When they don't receive enough light they get pale and leggy.

Day-neutral plants, including foliage plants, geraniums, coleus and African violets, are usually satisfied with 8 to 12 hours of light all year-round.

The intensity of grow light

The intensity of light that a plant receives is determined by the brightness of the grow lights and by how close the plant is to the light source. Plants differ in their need for light intensity. The best approach is to mimic the environment that plants naturally grow as close as possible. Typically, those plants that are native to tropical jungles or shady forests do not require much light. While plants that evolved in dry, sunny climates, such as the Mediterranean or southern Mexico require more light.

Some flowering houseplants, such as orchids and anthurium, are happy being 25 to 30 cm away from a light source. Foliage plants, such as ivy or philodendron, can be placed as much as 90 cm away from a light source.

But many flowering plants, such as orchids, gardenias and citrus, as well as most vegetable plants, require a much higher light intensity to flower and produce fruit.

Our custom made T5 grow lights provide bright, powerful light with 192 pcs of LEDs for 4 strips 1 (not many grow lights have this number of LED chips). They are also extremely efficient consuming very little electricity allowing you to save money. This is one of the best types of lights you can use to grow any kind of plant, from vegetables to the most delicate flowers.

The good thing is that the intensity of our grow lights can be adjusted. The best way to do this is to test out a few options, your plant will tell you when its just right! We suggest starting on a dim setting and building up to the brightest setting, this will allow your plants time to adjust. If you see your plant leaves "burning" or browning, reduce the light intensity.  You can also set up a timer for 3 hours, 6 hours or 12 hours.

Tips for using grow lights

Also consider the natural environment of the plant you are growing - indoor plants may not need much supplementary light, whereas something like basil will need a lot. A few general tips for using our grow lights:

  • Ensure the light stays at least 10cm away from any leaves (so as to not burn the leaves).
  • Adjust the timer to suit your plant's needs
    • 12hrs for plants in spaces with low light levels
    • 9hrs for spaces which receive indirect natural light
    • 3hrs for plants in high natural light environments.

Signs the light is too close or too strong

There are some signs telling you need to adjust your light intensity:

  • Burn marks on the leaves; this should only happen if the light is touching the leaves, or you’ve got very sensitive plants (reduce the intensity)
  • Crispiness/ browning edges (reduce the intensity)
  • Drooping leaves (reduce the intensity)
  • Stalky and leggy plants (increase the intensity)
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