yellow leaves on seedlings - advice needed

pierre_de_gaye

Hi all,

Please see below photos.   You'll note yellow leaf margins on the newest delphinium leaves, and also some similar issues with a chrysanthemum and several petunia seedlings.

They were potted on into good quality compost, and as far as i'm aware, i haven't been overwatering.   I tried to spray the petunias with a foliar solution of 'formulex' in order to fertilise, though this has had no impact.    I've read that young seedlings don't require any additional fertiliser anyhow until a lot bigger, and that the new compost should keep them well fed anyhow.

Hope to get some good advice here.     They are being raised under grow lights (although in a fairly dull room with only a small window), and receive 6 hrs of additional lighting.    Interestingly, a single pot of many petunia seedlings I have growing in natural light (a brighter room, also a bit warmer) does not house any yellow leafed seedlings.

Apart from the species mentioned here, all others seem to be doing very well under these conditions.

Thanks in advance.

PdG

Hostafan1

They look just fine to me.

pierre_de_gaye

But what about the yellowing of the margins etc?

floraltips

I too think they look ok. The only thing I would question is the amount of light. I have seedlings under lights  and they get 14 hrs because I read  somewhere that's what they need. Dull room + gloomy day = not enough light.

pierre_de_gaye

It's just the extra expense of keeping them on for double what they are now.    I can't afford nice LED replacements unfortunately.

floraltips

Get some cardboard, cover with foil, shiney side out, and set inside your trays creating an open ended box effect. Theory is the foil reflects light. Swap daily ( for better light) with the other seedlings that are doing well.
I'm sure they'll be fine in the long run.