hi

these plants are being grown in soil, ive always grown in hydro and have no idea what is the cause of this.

thanks in advance

hi, the plants are grown in soil and that leaf is one of the bottom sets of fan leaves. its multi purpose compost and perlite 50% 50%. the plants are up to the 10th internode and very healthy other than the bottom couple of internodes. none of the other plants are doing this but this one seems to be. its clear there is some type of nutrient problem, from the sick plant thing, the closest thing it looks like to me is a ph problem. i only water with plain water is this the problem, should i be ph'ing the water down from 7 to 5.8 to feed ? because i havent, thanks

bumpity bump - plz help

Doubt it will be a Ph problem, it does look like light burn to me i had it on my last lot and it was light burn but it didnt show for a while then when they were a bit bigger i noticed it coming through on the old leaves

Hiya JN,

Don't PH the water, the compost will buffer it.
50% perlite and a plant with 10 nodes, does not leave much food in the compost, might be hungry. Perlite is used mainly for cuttings, seedlings or to keep moister in the bottom of a propagator. The days of 50% compost and 50% perlite went out a long time ago, the perlite is inert and is taking up space that compost could take up and you might not have this problem.

Good luck,
GG

Hello JM,
If its just the bottom set of leaves it could be where you've spilt water on them, did it become progressive or as it always been the same effected area ?
Rj

Stagment Water standing on the leaf can act as a magnifying glass , burning the leaf where it was spilt onto (that’s a load of rubbish off the top of my head ) , but it does look light burnt tho !

That's what I reckon too. Something that doesn't generally happen in hydro but happens a lot with watering cans.

I had that problem too and it was basically light burn from leaving water on the leaf under the hps. it dont look like a nute prob or anything as nute burn allways causes burnt tips and that leaf aint got burned tips so it looks like splash burn m8. just leave the plant to it no need to flush or anything just carry on as normal m8.

you guys rock, and you are right, its from watering on the leaves which i have been doing.

also after reading up about perlite and compost and "old myths" i realise i shouldnt of used 50%.

thanks for everyones advice