Tomato seedlings - am I doing something wrong?

[rambleberry]

On most of my tomato seedlings and young plants, their oldest leaves are 'collapsing' at the edges. When this has spread over the entire leaf, the process then begins on the next oldest leaf, and so on.
I initially worried it was some sort of fungus, but the leaves on the older plants are now turning yellow and the edges are distinctly brown and crispy.

They have all been grown in compost from seed, re-potted once or twice, and fed once after potting-on with seaweed at the appropriate dilution for seedlings. They have been kept at a steady temperature of between 15-20ish degrees c, and were initially grown under LED light, and then moved into the porch. Other than this, the plants look ok and have been growing well, just not as green as I'd like, but we've had such atrocious weather for the last month that I'm not really surprised they look a bit 'pasty'.

However, my chillies, peppers and aubergines have all been grown in the same way and are all completely fine and don't show any similar symptoms.

What on earth is going-on? Or am I panicking unnecessarily and some sunshine in the next few days will sort them out?

[nickdub]

Tops and centers of the plants look OK - I'm not sure why the lower leaves have problems, but I reckon the plants will grow on fine, once the weather warms up.

[Scarlet]

Have they got an aphid invasion? Can you check all under the leaves....maybe with a magnifying glass.

[Bex2012]

I always thought the oldest leaves on toms always did die off, starting with the seedling leaves. Have those leaves been up against glass or squashed in some way? If not, id just snip them off and not worry about them, especially as the rest of the plant looks fine.

[Deano's "Diggin It"]

I'd be in agreance with Bex to be honest, looks like leaf scorch to me too, weather being from cold or heat, and I'd do the same, nip em off and with the weather now eventually warming let em get on with it!

[ESBkevin]

As stated above the old starter leaves will die, also tomatos can be hungry feeders once they get established. It might soon be time to introduce some nettle tea, BFB or a weak commercial tomato feed depending on what the compost used for potting was like. Not too much yet though.

[Jungle Jane]

Older leaves are sacrificed by the tomato plant to feed the new growth,the new leaves take the nutrition that’s why your new growth looks good,I wouldn’t cut the leaf off as it’s still green or the next oldest leaf will be used in the same way but you could cut that dead brown bit off. Are you putting them outside now?

[rambleberry]

Tops and centers of the plants look OK - I'm not sure why the lower leaves have problems, but I reckon the plants will grow on fine, once the weather warms up.

The good new growth is what is giving me hope that they're not suddenly going to keel-over.

Have they got an aphid invasion? Can you check all under the leaves....maybe with a magnifying glass.

Definitely no aphids; they're on the kitchen windowsill, munching on my oregano cuttings

I always thought the oldest leaves on toms always did die off, starting with the seedling leaves.

Well, yes, which is why I wasn't concerned initially, and I did pinch the seed leaves off several plants, but then it started spreading to the 'true' leaves, one after another, and I promptly panicked!

[rambleberry]

Older leaves are sacrificed by the tomato plant to feed the new growth,the new leaves take the nutrition that’s why your new growth looks good,I wouldn’t cut the leaf off as it’s still green or the next oldest leaf will be used in the same way but you could cut that dead brown bit off. Are you putting them outside now?

The larger ones (last 2 photos) have been in the greenhouse for a couple of days. I'll probably move more of the next-oldest ones out there in this warm spell we're meant to be having(!)


I'm wondering if this could be - somehow - some sort of nutrient burn, and the tomatoes have just been more sensitive than any of the other solanaceae?
This is the first year I've managed to grow them from seed (I've just bought plugs or plants in the past) and I keep worrying they're going to die on me.
Fingers crossed they'll look happier in a few days

[Jungle Jane]

Tomatoes do seem more sensitive than peppers & it’s all good experience whatever comes along,I just looked at the photo again did you check for aphids carefully look under the top leaves without touching the leaves if you can,there looks like specks of something?

[It never rains..it pours]

Personally think it look fine. Having so many this year, Im trialing them to justify keeping thirty nine and the non feed ones have dying lower leaves where as feed ones dont, imagine lower leaves die off to transport nutrients to new higher leaves. But as lower leaves are cut off when repotting not sure it makes any difference to end yield and most importantly the taste

[rambleberry]

Tomatoes do seem more sensitive than peppers & it’s all good experience whatever comes along,I just looked at the photo again did you check for aphids carefully look under the top leaves without touching the leaves if you can,there looks like specks of something?

I checked, and it's not aphids but compost?! No idea how I managed to get that stuck under the leaves, but there it is.

[marchogaeth]

Are you getting water on the leaves which is then causing scorch, if not close to the glass/polythene? IME the lower leaves do die but the senescence looks more natural than the black patches you are showing.

In any case, as others have said, keep them growing on well, feed and water at the bottom and they should be fine.

[rambleberry]

They look a lot better today. No spread of leaf collapse and lots of new growth, so I think the sunshine is doing them good.

[Gardener4Deaf]

I'm inclined to lean towards watering ( scorch burn) or when adding liquid nutrients the leaves are touching the wet soil?