What Are the Best Grow Lights for Starting Seeds Indoors?

Grow lights are no longer a specialist purchase — affordable, effective options are available for every budget. Whether you have a single windowsill tray or a dedicated growing shelf, supplemental lighting transforms seedling quality and allows you to start crops weeks earlier than natural light alone permits.

Full-Spectrum LED: The Best Choice for Most Growers

Modern full-spectrum LED grow lights are the top choice for seed starting. They produce light across the full visible spectrum — mimicking sunlight rather than emitting only red and blue wavelengths — which gives seedlings balanced, natural growth. LEDs run cool, use less electricity than any alternative, and last for tens of thousands of hours. Look for lights labelled "full spectrum" or "white LED grow light" rather than the old purple/pink "blurple" LEDs, which produce a more limited spectrum.

A single 40W full-spectrum LED panel will comfortably cover two standard seed trays (about 70×35 cm of growing area). For a dedicated shelf system, a strip LED fitting across the full width of each shelf is ideal.

T5 Fluorescent Tubes: Still a Solid Budget Option

T5 fluorescent tube fittings remain popular among gardeners who already own them or find them discounted. They are cooler-running than older tube types, produce useful light for seedlings, and are cheap to buy. The drawback is higher running costs than LED and shorter lifespan. If you are buying new, LED is almost always the better investment.

How Far Above the Seedlings?

This is where many growers go wrong. LED grow lights typically need to be positioned 10–20 cm above the tops of seedlings, not 50 cm away. Too far and light intensity drops sharply (light follows the inverse square law — double the distance, quarter the intensity). Start with the light 15 cm above the tray and raise it as seedlings grow. Use an adjustable hanging system so you can keep the correct distance throughout the growing period.

How Long to Run Grow Lights

For seed starting, run lights 16 hours on and 8 hours off. Plants need a dark period — continuous lighting causes stress in most species. Use a cheap plug-in timer so you do not have to remember to switch lights on and off. Set them to come on early in the morning and switch off by early evening.

Simple DIY Shelf Setup

A metal wire shelving unit with an LED strip mounted under each shelf is one of the most effective and affordable seed starting setups you can build. It requires no specialist knowledge and can be assembled in an hour. Three shelves give you six standard tray positions — enough to grow all your vegetable transplants for the season.