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Environment

Tall, leggy, weak seedlings

Seedlings shoot up tall and thin with long gaps between leaves, often falling over.

Commonly affects: All seedlings

What you'll see

  • Long, thin stems
  • Wide spacing between sets of leaves
  • Pale colour
  • Plants flop over

Likely causes

  • Light too far away or too weak
  • Light running too few hours per day
  • Temperatures too high (>26 °C) for the available light
  • Overcrowding in the seedling tray

How to fix it (step by step)

  1. 1Drop light closer (or use a stronger fixture) — for LEDs, 30–40 cm above the canopy
  2. 2Run lights 16–18 hours per day for seedlings
  3. 3Lower the air temperature into the 20–24 °C range
  4. 4Thin seedlings so each one has space
  5. 5Gently brush the tops of seedlings 2–3 times a day to thicken stems

Stop it happening again

  • Strong light from day one of germination
  • Don't sow too densely

Need a second opinion?

Share dated photos, root observations, water readings and your mixing record so our team can assess the problem. Visual symptoms alone do not confirm a diagnosis.

Confirm the cause before treating the crop

Collect observations that distinguish possible causes

Record the first appearance of symptoms, the affected plants and whether old or new tissue is involved. Inspect roots, delivery and visible pests. Compare a healthy plant nearby. Record pH, EC, temperature and recent changes. Several causes may act together; the symptom title is a starting point, not a confirmed diagnosis.

Verify calibration and the complete mixing record. Product links explain nutrient roles; they are not instructions to use one bottle alone. Record your correction and assess subsequent growth because damaged leaves and fruit may not recover.

Escalate safely

Rapid wilting, collapse or spreading root symptoms need prompt checks of flow, oxygen and hygiene. Protect unaffected plants where practical and seek qualified diagnosis. Treatments must be registered for their intended crop and use and applied according to label, including harvest intervals.

When asking for help, provide dated root and leaf photos, water readings and mixing records. Do not combine nutrient changes with disinfectants or pesticides without compatibility advice. An online guide cannot confirm a pathogen or prescribe a universal chemical treatment.

Further reading

These sources support general cultivation guidance, not verified Nana Organics product performance. Current NaO instructions take precedence over another brand’s feeding schedule.