How long does cannabis nutrient burn take to cure?

Mild nutrient burn clears in 7 to 14 days. Moderate burn takes 14 to 21 days. Severe burn takes 3 to 5 weeks. Brown tips stay brown. New leaves show recovery.

Fulvic Acid for Cannabis: A Guide to Mitigating Nutrient Damage

Three factors set the time: how much leaf damage exists, the grow medium, and how fast you lower nutrient strength.

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Signs of nutrient burn

Step 1: Stop the nutrient solution

Mix no new feed. Water with pH-adjusted water for the next 2 to 3 days. In soil, let the pot dry between waterings.

nutrient burn vs nitrogen toxicity in cannabis

Step 2: Flush the root zone

In soil, run water at pH 6.0 to 6.5 through the pot. Use 2 to 3 times the pot volume. In coco or hydro, drop EC to 0.8 to 1.2 for 3 to 5 days.

cannabis nutrient burn cure time

Step 3: Read runoff numbers

Catch runoff and test EC or PPM. If runoff EC sits 0.4 or more above the input EC, salts have built up. Flush again and retest.

Step 4: Restart at half strength

Wait for new leaves to show normal color. Mix at 50% of the last dose. Raise the dose by 10% every 3 to 4 days. Keep pH in range for your medium.

Step 5: Cut dead tissue

Remove leaves that are more than half brown. Dead tissue holds no chlorophyll and can harbor mold in dense buds.

Recovery timeline by damage level

What slows recovery

When to check for other problems

Brown tips can come from dry air, salt buildup, or root rot. Check runoff EC, root color, and humidity. Root rot shows brown roots and a sour smell. Nutrient burn shows brown tips with dark green leaves and no root decay.