What does too much nitrogen (the claw) look like?

Leaves are very dark green, almost shiny. Leaf tips bend down like a claw while the leaf stays turgid. Stems look weak for the size of the leaves. In early flower, buds form slowly while leaves keep growing.

How do I prevent too much nitrogen (the claw)?

Start any new nutrient at half the label dose and go up only if the plant asks for it. Change to bloom nutrients when the stretch starts.

Plant problems · Nutrients · Vegetative growth · Act this week

Too much nitrogen (the claw)

What you see

Leaves are very dark green, almost shiny
Leaf tips bend down like a claw while the leaf stays turgid
Stems look weak for the size of the leaves
In early flower, buds form slowly while leaves keep growing

Why it happens

The plant gets more nitrogen than it can use, often from strong grow nutrients, hot soil mixes or keeping the veg feed into flower.

What to do

Cut the nitrogen: feed plain pH adjusted water once, then go back at half strength
If you are in flower, switch to a bloom nutrient
In coco or hydro, give a light flush with pH adjusted water and some runoff
New leaves should come in a normal green within a week or two

Next time

Start any new nutrient at half the label dose and go up only if the plant asks for it
Change to bloom nutrients when the stretch starts

Easy to confuse with

Nutrient burn: Leaf tips turn yellow, then brown and crispy, a few millimetres in
Overwatering: The whole plant droops with leaves that feel firm and swollen, not limp
Heat stress: Leaves fold upwards along the middle like a taco

Not sure?

Take a photo of a fan leaf from the middle of the plant, side on, so the claw shows and ask the Grow Doctor, or send it to the grow companion on Telegram.