Seeds
Leggy Seedlings Are a Light Problem, Not a Watering Problem
The classic pale, stretched, floppy seedling is almost always starved for light intensity, even when it's sitting right in a bright window.
Seedlings respond to light intensity, not just presence of light. A sunny windowsill might feel bright to a human eye, but it delivers a small fraction of the light intensity outdoor sun provides, and light falls off sharply with distance from the source. The seedling responds by elongating its stem, reaching toward the light source in a stress response called etiolation — the classic leggy, pale, weak-stemmed seedling.
A grow light positioned 2-4 inches above the seedlings (adjusted upward as they grow) and run 14-16 hours a day corrects this reliably, since it delivers far more usable intensity than even a south-facing window. Rotating windowsill trays daily helps but rarely matches the light a proper setup provides.
Put this into practice
- Grow Light CalculatorHow high and how long should my grow light run?
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