Looks like transplant shock into cold soil. They will recover, eventually.

9C is cold for tomatoes, especially if the soil is still cold from winter, which is likely is. It effects the ability to uptake certain nutrients from the roots, and the leaves turn that black/purple. Happened to me last year, transplanting too early.

Oooh :(

They were just getting too big :( Ok, so I just wait for them to hopefully recover.

THANK YOU!

It's hard to say with the information given. But it might look like a lack of fertilizer and some damage from cold. Peter is probably right about the temperature, as this can also influence fertilization.

Cold ground can inhibit the assimilation of phosphate and turn the leaves a deep purple/black tint, especially towards the tips/edges and undersides. Yours is very minor and should be fine if that's all. If you can cover the ground with black plastic, it might stay warmer and get your plant in gear sooner. Roots after transplant are pretty useless initially so another idea is to use a shot of regular strength soluble fertilizer. In what region are you growing?

PC

The purplish tint is due to low phosphorous, but that is common with seedlings until they are in the soil and take up nutrient better so it should automatically go away. You do not need to have too much phosphorous in the soil because it will inhibit the plant from taking up other nutrients.

I would water it with a bit Epsom salt which will aid the growth. Mulching the soil the around the plant can help keep a more stable temperature in the soil as well. If it is cold where you are I would build a small green house for it using some cheap plastic, just make sure the afternoon sun don't burn it.

For me personally, I cut off the leaves in the bottom that are too close or touches the soil, this is to prevent them from getting wet and touching the soil which increases the chance of the plant picking up diseases.

This website is informative in showing what the tomato leaves look like with different nutrient deficiency: http://www.haifa-group.com/knowledge_center/crop_guides/tomato/plant_nutrition/nutrient_deficiency_symptoms/

Agree that it was far too cold to transplant them, especially without knowing what the soil temp was first. But it is too late now . I also hope the manure was VERY well composted/aged. If not that could pose a real problem for them. And if they were "quite big" and already blooming as shows in the photo when you bought them that will only make them less tolerant to transplant shock. If it turns out you have to replace them buy small plants without blooms on them. I would pinch those blooms off to reduce the stress on the plants and then wait and hope the weather grows warm quickly so they can adjust and recover.

Dave

I agree with above posts - transplant shock and nutrient problems associated with cold soil temps. The good news is that if you can keep them warm at night, they will probably bounce back. For all the fuss we make over them, tomatoes are pretty hardy plants.
Looking ahead, keep an eye on the soil in the pots so you don't overwater the plants. Soil from the ground tends to compact a lot in containers; a common recommendation in the forum is to use potting soil or potting mix when growing in containers. You're already committed for the season, so just keep an eye out for sufficient drainage and try to avoid soggy soil.
You don't mention where you are located but once the soil warms up and season is farther along a good layer of mulch on the soil will keep the temperatures from fluctuating and help keep more even soil moisture.

The blueing/dark color on the leaves indicate to me that the plants are not getting/uptaking nutrients adequately .
In my opinion 9C (=48F) was not and is not cold for tomato plants PROVDED you hardened them off , for several days, prior to planting.

The second issue is the soil temperatures. In order for the plants to be able to uptake nutrients, a minimum soil temperature is required . 50 -55F ? ( = 12 C) should be ok. Again, in the hardening off process the roots also are introduced to cool temperatures gradually, so when they are placed in cool soil ( 10 -12C) they won't get a shock..

MY Recent Experience:
On 4/8, 9, 10/15 I planted bunch of tomato plants, some with protection some withoiut. In the following week we had lows going down to 38F ( =3.5 C) .few nights. I have seen no ill effects. BUT before planting out I did check the soil temperature. It average around 52F.
So far our average lows have been 42-43F. My plants are normal, though they are growing very slowly. I have seen buds on several of them.

I think your plants should rebound. I would water them with lukewarm water (~ 26-27C). When I want to water mine, i fill watering cans and let the warm up in the sun for several hours. Warmer water will raise soil temperature and help dissolve the nutrients better for the plants uptake. JMO

Sey

Thank you guys for all the advice... :) :) :)

I supposedly hardened the plants before planting outside and I also mixed the soil that i dug from the ground with store bought soil, so I thought it would not be cold... I don't have a thermometer for the soil, so I'm just guessing

I am located in Europe - Bulgaria to be exact.... Here tomatoes are usually planted outside in the beginning of MAY.

Maybe, as you guys said, the plants were just too big and they are having a tougher time adjusting :/ Well, I hope for the best!!!

I cover them with plastic wrap in the afternoon until morning... I also checked the soil and it doesn't seem too moist...

BUT yeah.. they definitely look like the ones that lack phosphorus!!! I can see the dark veins on the leafs.

THANK YOU AGAIN!!! If they get better, I'll send some tomato pics :D

Regards!!!

Maria

You may be able to help warm things up with a simple black garbage bag. Cut it down the sides to make one long strip of plastic. Cut a slit in the middle to go around the plants stem. Then lay it so that it is fairly flat on the ground, and weigh it down in a few spots with some heavy rocks or bricks. You may have to cut enough away from the stem area to be able to water the plant. This will help to warm the soil a few degrees during the day.