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Gothic Arch Greenhouses understands that grow lighting can be one of the most essential factors to successful plant production in a greenhouse. Grow lights help to lighten shady spots and propagation areas in the greenhouse. Whether you are growing plants for your own enjoyment or are producing for the commercial market, adding supplemental greenhouse lighting can be a huge benefit for your plants.

Grow lights are essential for greenhouses as they provide the necessary light intensity and spectral range needed for optimal plant growth. Without these lights, plants would struggle to thrive and produce at their full potential. Grow lights also provide an additional layer of protection in greenhouses as they can help prevent temperature fluctuations and keep the environment more stable. Additionally, they can be used to extend the growing season further into the colder months when natural daylight hours begin to diminish.

How to choose greenhouse grow lighting:

  • How much is natural sunlight available?
  • What type of crop is being grown?
  • Is there adequate room to mount your lighting?
  • What are your growth goals?

Assessing Your Lighting Needs

Greenhouse plants require a minimum of 6 hours of direct, full-spectrum sunlight per day. Grow lights should be used to supplement solar exposure if plants receive less than this, or if your growing goals require additional light to trigger early flowering, higher yields, taller plants, and the like. For example, in a vegetative stage of plant growth with no natural sunlight, 14-18 hours a day of supplemental light is ideal. If you are actively fruiting and flowering, most plants thrive at 12 hours of light per day. Determine how much supplemental lighting you will need in a day and the energy required to help decide which lights are right for you.

Different crops have different lighting needs. Fruiting plants typically need more light and must be spaced to allow proper light penetration and avoid small fruit size due to lack of even light. Plants grown for their vegetation, such as herbs and lettuces, require less light because they are kept in the “leafy” growth stage for their life cycle. Tropical flowering plants generally require a full 8 hours of strong, full-spectrum light per day. Additionally, CFL grows lights, LED lighting, High-Pressure Sodium (HPS), Metal Halide (MH), and T5 Fluorescent lighting offer different light spectrums, lumens, and energy use.

Plants need to have room for growth while still getting optimum light penetration. High pressure sodium lights should be mounted 30 to 36 inches above the plant, while our T5 Fluorescent Lamp produces minimal heat and can safely be placed within 6 to 12 inches of greenhouse plants. Ceramic metal halide lights should mount 30 inches over your plants and are ideal for hydroponic applications.

Although plants love light, care should be taken not to use too powerful a light in a small space, which can result in overheating of the leaf surface area. When mounting your lighting fixture take into account the type of light, its heat output, and how tall your plants will grow. A simple rule is "if it is comfortable for the back of your hand, it will be a safe distance for your plants"

When considering your growing goals, your grow lighting can help you achieve responses such as darkened leaves, healthier-looking greenery, prolonged blooming, higher yields, extended growing season, and more. Younger plants typically require less light than older plants. As crops mature and become more developed, they should receive more light to ensure proper blooming. Studies have shown that a broader color spectrum lamp will perform much better than a lamp with high lumen output, especially when it comes to planting growth.

Gothic Arch Greenhouses offers the latest technologies in greenhouse lighting systems, along with over 70 years of horticultural experience. For expert advice, a great selection, and a fair price, look no further. From backyard hobby greenhouses to full commercial production houses, Gothic Arch Greenhouses can meet your lighting needs and recommend the ideal system for your climate, crop, and budget. Call one of our residential or commercial experts today at 1-800-531-4769.