Lighting Time: A Gardener’s Guide to New Grow Lights | gardening tips

PThe next generation of grow lights are showing up in living rooms across the country, and certainly as questions in my inbox. An amazing tool, these can be a conundrum to many. So here’s a quick guide to cutting through the confusion.

First of all. The concept of grow lights is not really new. In order to stimulate plant growth in areas with little natural light, they have been around since at least the early 1980s. The problem is that until very recently they were huge, incredibly complex to set up, and gave off so much heat that, ironically, they could often burn the very foliage they were trying to feed. That’s before we considered their exorbitant cost, not only to buy but also to operate. We were talking over £200 to buy a single incredibly energy efficient bulb.

However, that all started to change about 10 years ago when a new generation of LED lights started hitting the market. Using a fraction of the energy and emitting very little heat, these products have steadily decreased in size and price over the years. You can now buy bulbs that will fit any standard desk lamp for a little more than the price of regular bulbs. Even flexible LED strips can be glued in place to line the underside of shelves, cabinets and larger terrariums.

As almost all houseplants should be grown within 2m of a window, these lights open up vastly new opportunities for indoor growers – and even for regular gardeners who grow many tender or semi-hardy from seeds, like tomatoes. Without a greenhouse, grow lights are really the only way to keep significant amounts of seedlings away at this time of year.

This sudden boom means that there are now so many options available in different shapes, forms and colors that it can be a bit confusing. Generally, the most important thing to remember is that plants grow in any light that humans can see. However, they have preferred spectra, which mostly appear blue or red to our eyes.

That’s why many grow lights have crazy disco hues, and many even have adjustable features to change their color. That’s because changing the wavelengths of light that plants sense can, surprisingly, change their behavior. For example, increasing certain wavelengths of UV can cause cannabis to expel more resins, or infrared can make commercial tomato crops grow more fruit.

However, are they really relevant for home growers who just want the plants to look good? No. Can you even see the true colors of a plant under colored lights? No. Do they fit with most people’s idea of ​​what they want their living room to look like? Probably not. So I would always avoid them in favor of the simpler options that emit white light. Frankly, even regular daylight bulbs will work fine.

So please don’t feel confused, just choose the options that fit your budget and see how your indoor growing opportunities will suddenly expand.

Follow Jack on Twitter @Botanygeek

Terri S. Tomasini