Artificial Lighting for Orchids: Part Two – Choosing the Right Type of Light!

In this second article on artificial lighting, we will focus on the lighting technology best suited to implementing the principles outlined in our first publication.

Led Artificial Lighting Is the Only One Worth Your Investment.

In the past, there were incandescent bulbs, fluorescent tubes, halogen lights, sodium vapor bulbs, and mercury vapor lamps. Don’t buy any of these. These technologies are outdated, energy-intensive, expensive, and polluting. Most of them are also banned (from sale) in several European countries. If you have this type of lighting and it still works well, you can continue to use it, but plan to replace it eventually. Your plants will quickly thank you by showing an eloquent burst of vigor once they have tasted the excellent lighting provided by light-emitting diodes (LEDs).

LED Lights

LED lights (or Light Emitting Diodes) have revolutionized the world of horticulture by offering lighting options that are economical, environmentally friendly (2 to 3 times less electricity consumption for the same brightness), much more durable, and largely recyclable (approximately 80 to 90% of their materials are recyclable). In addition, they are compact and take up little space on growing shelves.

But that’s not all: LED lights produce near-ideal lighting for growing plants. All the wavelengths necessary for photosynthesis are present in the LED light spectrum, in proportions that are very well balanced to promote plant growth.

However, there are a few details to keep in mind in order to maximize their effectiveness.

Focus Your Artificial Lighting on Growing Areas

This is the most common mistake made in home installations. It’s not surprising, since hardware store lights are designed to illuminate an entire room. But that’s not what we’re looking for in horticulture. On the contrary, the light produced must be concentrated on the growing space so as not to disperse the energy that is so precious to plant growth.

To focus the lighting on the growing areas, it is advisable to maintain a short distance between the plants and the lighting system. A spacing of 5 to 10 cm (2 to 4 inches) is more than sufficient when using LED fixtures that generate little heat. The main disadvantage of these short distances is poor air circulation, which leads to heat buildup, which is clearly undesirable. Handling the plants can also be a little more difficult.

If you want to increase the spacing between plants and fixtures, it is highly recommended to use fixtures with side reflectors. These reflectors help contain the light and optimize lighting efficiency.

DIY Solution

Another effective solution to prevent light dispersion is to build a box around the light fixtures and equip it with an anti-dispersion grid. These reflective grids are available at hardware stores in the suspended ceiling accessories section. They are very effective and inexpensive. When purchasing, ask the sales assistant to show you which way to install it for optimal effectiveness. Some anti-scatter grids are not symmetrical and must be installed in the correct direction.

If you’re not handy, buy grow shelves with built-in reflectors and follow the manufacturer’s instructions for safe installation! This isn’t the most economical solution, but it greatly simplifies the creation of a quality growing space. Large hardware stores and garden centers usually offer this type of horticultural lighting equipment. I recommend making a rough plan before going to the store and making sure that the salesperson has a minimum of expertise in horticultural lighting. This will ensure you get the best advice.

Select Full-Spectrum Led Lamps

Full-spectrum LED lights mimic natural sunlight and are ideal for orchids. They provide a good balance between the wavelengths needed for plant growth and the hygiene of growing spaces. Look for lights labeled “cool white” or 6,000°K or 6,500°K. These are sometimes referred to as horticultural or photographic lights. They are not necessarily easy to find in hardware stores, as domestic lighting mainly uses “warm white” LEDs (i.e., 4,000°K or even 3,000°K), which are less irritating to the eyes. However, these are less stimulating for plant growth.

Online

If you are having trouble finding the right product in stores, there are several reliable online sources that specialize in horticultural and photographic lighting. Focus your search on cool white spectrum lights, or 6,000°K or 6,500°K lights. This technology is best suited for a mixed collection of orchids and houseplants.

Not only will your plants benefit from the best lighting, but you will also be able to appreciate the natural color of your flowers under cool white lighting. Warm lighting tends to give certain flowers a yellowish tint, especially the paler ones.

To determine the number of tubes to use, you need to consider the specific needs of your collection and the clearance between the plants and the lighting system. This will be the topic of our next column.

Note de l’éditeur

Les chroniques de M. Charpentier sur les orchidées sont publiées sur le site du Jardinier paresseux dans un modèle légal «libre de droits». Les sociétés horticoles qui le souhaitent peuvent republier ses chroniques dans leur journal technique. Veuillez toutefois inclure la mention suivante: 

Cet article a initialement été publié en français sur le site internet du JardinierParesseux.com et en version anglaise sur le blogue LaidBackGardener.