Tomato plant help

[treepixie]

My tomato plants are not doing well this year, they are looking very spindly and are a light green in colour and some of the leaves are dying.

They are in mPC and are watered from the bottom and are under grow lights.

The chillies that are in the same mPC are doing really well.

Any ideas what could be wrong

[Penellype]

My Shirleys are almost exactly the same - I was wondering if they are too hot. But the Balconi yellow (much smaller plants at the moment) are fine. I have no explanation I'm afraid, but you are not alone!

[veggiechicken]

It looks like a nutrient deficiency of some sort. How long have the plants been in the same compost? Longer than 6 weeks??

[nickdub]

try them with something like seaweed feed - if its a nutrient problem they shpould green up pretty quickly.

[Penellype]

Mine germinated on 23rd Jan and are in tomato gro-bag compost. I'd not normally feed before potting on into a bigger pot - they are not quite big enough for that yet. They have been looking yellow almost from the start and have developed the wilted leaves recently.

[Dynamite]

Does it look like over watering?

Regards........Rob

[Penellype]

Does it look like over watering?

Regards........Rob

Mine are on capillary matting with a water reservoir underneath, so over (or under) watering is highly unlikely.

[treepixie]

They are in new compost, so should be getting enough nutrients, it's really weird as my chillies are in the same compost and are dark green and growing well.

[bramble]

A few of my tomato seedlings started to look a bit pale so I mixed up some Epsom salts and watered it in.
I also had some granular feed left over from last year so added that as well.
They are growing fine now and look a lot healthier.

[hop-a-long]

I've had the same problem with my tomatoes too, about 5 weeks old now. I thought the light mightve been too strong and started crisping them up a bit so I moved them onto the window sill. But as you said, chillies and (ridiculously early) cucumbers are looking fine. I also figured they must've run out of feed or maybe the batch of mpc I used was particularly low in nutrients so I mixed up a dash of 25:15:15 +te feed which looks to have helped them a bit.
Never noticed problems like this at this young stage before though- maybe a dodgy compost blend?

[Penellype]

If feeding them seems to help it sounds as though the compost is low on nutrients. I'm going to pot my 2 up this weekend,

[treepixie]

I had already potted mine on and it made no difference

[Penellype]

Strange. I was wondering whether wide swings in temperature could be the culprit - it gets quite warm under the grow light and the room is heated, but can get quite cool at night. However, that doesn't explain why the balconi yellow plants are ok.

Its a puzzle.

[treepixie]

And why the chillies are fine! Are they more tolerant of lower temps?

But maybe as you say with the temps we have been having once the lights are off and the heating is off, it's far to cold for them, I think you might have the answer.

[WalterWhite]

Not an ideal NPK ratio for tomatoes! Lower ratios need across all nutrients and the phosphorous value should be higher than the nitrogen.