Growing conditions

Not enough light (stretching)

Seedlings and plants in low light stretch toward it, building long, weak stems.

Signs

• Long gaps between leaves; thin, pale stems that flop.
• Leaning toward the window or the lamp.

What favors it

Window light in winter, lamps too far away or too dim, and seedlings kept too warm for the light they get.

Prevention

• Give seedlings bright light from emergence; a few inches under LED shop lights or a seedling light.
• Keep nights cooler than days to hold seedlings shorter.
• Brush seedlings when the leaves are dry to firm stems.

Often confused with

Sources

• Low Light Impacts on Indoor PlantsUniversity of Maryland Extension
• Starting seeds indoorsUniversity of Minnesota Extension
• Grow Lights for Starting Seeds IndoorsUniversity of Maryland Extension
• Managing Plant Height of Vegetable TransplantsUConn Extension IPM

Why →