Young tomato plant pale green leaves - any ideas?

[Overawy]

Hi,

I'm a relatively new gardener as this will be my 3rd season.

I've got several variety's of tomato's growing on a south facing windowsill. Originally they were in 3 inch pots and were potted up 2 weeks ago into 5/6 inch pots.

In the last week they seem to have all taken a turn for the worst, the leaves are starting to go pale green and look a bit sad for themselves (see attached pics) - this is happening on all 6 plants

I've never had this happen in previous years

I've had a read and think it might be a magnesium deficiency so was going to give them a liquid tomato feed and a spray of Epsom Salts (along with getting some more seeds planted just in case!)

Can anyone confirm if I'm taking the right course of action?

Much appreciated

Lee

[Gillykat]

Last year was my first ever attempt at growing tomatoes (Gardener's Delight) and mine were quite pale looking too when they got to the size your's look to be. Mine were on a south-facing living room window so I thought it would be sunny enough but I was advised by a few folk on here that the paleness was caused by not enough light. I transferred them to the greenhouse on my allotment and within a week they were getting a more normal dark green colour. In late-May I transferred them to the polytunnel and had a fabulous crop from them

Other than them not getting quite enough light I don't know what to suggest but I know someone will be along soon who does! I'm sure yours will be fine. Which part of the country do you live in? I'm in Northumberland and last year sowed my tomatoes on March 3rd which was a tad too early. This year I waited until last Saturday, 2nd April and they're all germinating nicely now

[Zelenina]

I'm not an expert, but it does look to me like a deficiency of something. There are several kinds of deficiencies that can cause yellowing of leaves, but with the yellowing mainly between the the veins, it could well be lack of magnesium as you guessed.

What did you fill the pots with when you repotted them? I wonder did you get a dud batch of potting compost. I think the general tomato feed is a good idea because it may just be that the Mg has run out first and other things are nearly gone too.

A tomato feed should contain magnesium, although I've read that some don't, so check the info on the bottle. You might not need the Epsom salts as well. Or you could experiment with Epsom salts on some, tomato feed on some, and both on some to see which gives you the best results.

[jackarmy]

Were they recently repotted?.look to be in a bit of shock to me.
A touch of feed shouldnt do any harm.

[Overawy]

They were repotted around 1.5/2 weeks ago in a general multi purpose compost.

I did add a little blood fish and bone to each pot during repotting.

Thanks

[MarkPelican]

To be honest, they don't look too bad to me. I think its unlikely to be magnesium efficiency at this stage of the season. If it is, then looking at what you've written it could be too much TLC. Magnesium efficiency can be caused by too much potassium - which could be in the BFB you added - (the tomatoes take up potassium in preference to magnesium).

A touch of nitrogen fertiliser or epsom salt won't harm them but make sure they're kept warm and damp (not too wet).

BTW different varieties can have different colour leaves.

[Jungle Jane]

Have you used BFB in pots before? I'm wondering if they're over fertilised & how much BFB was used for measurements a pinch would be ok at the bottom of the pot but also If it was fresh compost that will also have fertiliser in it. Too much salts from fertilisers can make it difficult for the plant to absorb water. My plants stay in the 3" pots until they're planted out in may,they can get to about 1-2 foot tall,were the plant roots coming out the bottom of the pot? If not they could have stayed in the 3" pot?

[Martin H]

I think they are suffering from indigestion caused by too much tlc. I suggest a few weeks of benign neglect while they sort themselves out. Water them when they dry out but otherwise leave them alone. They'll be fine.

[bario1]

I suspect the bfb as well... last year I mixed it into my final potting up mix for my aubergines, and they went steadily downhill from there, with limp leaves despite having plenty of water. When using bfb it's suggested that you add it to your beds a couple of weeks before planting so it can break down a bit - adding it to a potting mix is a gamble (one that I won't be taking again) as you're probably adding way too high a concentrate even if it's just a pinch or two.

[Overawy]

Yeah the roots were just poking through the bottom in the 3 inch pots and I put a couple of pinch's of BFB into each pot.

First year I have tried putting the BFB in. Maybe this is the cause then?

What's the best course of action to save them? A thorough soaking to flush out the fertilizer, repot them with new compost or leave alone?

Thanks for all the help

[bario1]

Personally I'd re-pot with fresh compost, but try not to disturb the rootball too much, just replace the compost in the bottom and sides of the pot.

[Jungle Jane]

I don't know if flushing would help it's a slow release fertiliser,I can imagine the plant suffering more,I'd repot them if they were mine because theres been no improvements for so long after they were repotted,they usually only sulk for about a day. They should be flourishing with the extra pot space. If unsure repot a couple & see if it helps?

[Overawy]

I best get repotting then I think!, I'll post in a few days time and let you know how there getting on.

Thank you to everyone for your help, If anybody has any other idea's/comments then please do so!

Lee

[Chris11]

What looks like a nutrient deficiency can be caused by other things than an actual deficiency. Temperature, pH, and even too much of some nutrients can all affect a plants ability to use the nutrients available.

Looking at the pictures, the veins look green, but there is yellowing of the leaves between the veins. So I would say this looks like interveinal chlorosis (lack of chlorophyll), but that doesn't necessarily mean a magnesium deficiency.

I'd agree with others it was probably too much BFB. An excess of Nitrogen can prevent the plants uptake of other nutrients, and as Mark says, excess of Potassium at this stage could prevent uptake of Magnesium.

If the plants are already a bit weak, I'd be cautious about repotting them and causing more stress. Hopefully plain watering and no more feeding will give them chance to recover.

[Gillykat]

Great advice (as usual! ). I wasn't even aware that BFB ~ or any fertiliser ~ could have an adverse affect so I've learnt something from this myself