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Grow lights for earlier crops

Boosting light levels early in the season

No, it’s not Studio 54, it’s my conservatory in February using grow lights. I started using one a few years ago, for my early seedlings. I’d been toying with the idea for a while. Even though the conservatory has good light, a few extra hours a day or to boost dull days is a real help.

UPDATE: With the massive hike in energy bills, I’ve decided to pack mine away and sow my seeds later, using the natural increase in daylight as the days lengthen. If you decide you still want to use one, here’s my advice:

Grow light in the conservatory over sweet peas, tomatoes and Echiums
Grow light in the conservatory over sweet peas, tomatoes, and Echiums

Grow lights did prove handy. Plants were further on, especially sweet peas and tomatoes. Unfortunately, during my first year of use, we also had a cold April which led to a logjam in the conservatory and greenhouse. Well, you can’t have everything.

“We’ll be having a visit from the drugs squad,” moaned the other half.

It also meant I could stagger my sowings even earlier. I bought four different types of Echiums, which ended up taking up a lot of room. It also means there’s less chance of legginess with early seeds, like half-hardy annuals, tomatoes, and sweet peas.

Three blue and nine red bulbs
Three blue and nine red bulbs

Grow lights can be used to supplement natural light if there’s not enough sun; as the sole source of lighting, or during propagation.

It’s important to note this is not an ordinary light bulb – there are red, blue and orange-red elements. The red and blue parts of the spectrum are for compact foliage growth, while orange-red simulates noontime sun and encourages flowering. As I wanted sturdy plants, my bulb is red and blue.

My bulb was under £16 (LED Plant Grow Light, THZY 12W, E27, 3 Bands) and it fits into a desk lamp with an E27 fitting. It’s not available anymore but you can get more advanced ones from Amazon. I bought a tall lamp with a clamp fitting for £15. This means you don’t have to invest in a permanent fixture and it’s moveable.

Obviously, make sure there’s a plug nearby but out of the way of any potential water spillages. I used a basic light timer, giving the plants 12 hours of daylight, until the end of March. This can be increased to about 16 hours, but plants also require at least eight hours of darkness each day. For seedlings/cuttings, the light source needs to be placed as close as possible to the plants.

Potted guide: grow lights

Potted guide
  • NAME AND PRICE: LED Plant Grow Light, THZY 12W LED Plant Grow Light For Hydroponic Garden Greenhouse (E27, 3 Bands).
  • BULBS: 12 LEDs (3 blue & 9 red).
  • FEATURES: Low power consumption, does not generate noticeable heat.
  • TECHY STUFF: Emits the wavelengths of light which can be fully absorbed by plants; 660 and 430nm; 630 and 460nm, four peaks of growth spectrum for maximum chlorophyll A and B production. Rich in red light for blooming and fruit and blue for promoting leaf growth.
  • OTHER EQUIPMENT: Fits standard E27 socket, a desk lamp will do.

Grow lights for earlier crops updated September 2022