Troubleshooting

Should You Use a Grow Light for Seedlings?

If your window gets less than 6 hours of direct sun, you need a grow light. A $30 LED shop light works for most seedlings.

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Should You Use a Grow Light for Seedlings?

If your window gets less than 6 hours of direct sun, you need a grow light. A $30 LED shop light works for most seedlings.

When You Need One

You need a grow light if:

  • Your window gets less than 6 hours of direct sun
  • You’re starting seeds in winter
  • Your seedlings are leggy and pale
  • Your window faces north

You don’t need one if:

  • You have a south-facing window with 6+ hours of sun
  • You’re starting seeds in spring/summer

What to Buy

TypeCostBest For
LED shop light$20-40Most seedlings
LED panel$30-60Larger setups
T5 fluorescent$50-80Serious growers

How to Use It

  1. Distance: 2-4 inches above top leaves.
  2. Duration: 12-16 hours per day.
  3. Timer: Use one.
  4. Adjust height: As plants grow, raise the light.

Signs You Need More Light

  • Seedlings are tall and thin (leggy)
  • Leaves are pale
  • Plants lean toward the light

Common Questions

Do I really need a grow light? If you have less than 6 hours of direct sun, yes.

Can I use a regular light bulb? No. Wrong spectrum.

How long should grow lights be on? 12-16 hours per day. Not 24.

How close should the light be? 2-4 inches for most seedlings.

Will grow lights make plants too hot? LEDs run cool. Fluorescents are warmer.

Do grow lights use a lot of electricity? No. A 20W LED runs about $0.02/day.

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