TOMATOES LEAVES GOING GREY SEEM TO BE LOSING THERE CHLOROPHYLL  ??

Put the plants out about 3 or more weeks ago but the above happened so dug them up repotted them and put them back into the conservatory problem sorted i.e. leaves stopped going grey (could say transparent). Thought the cause was the weather i.e. to cold/windy.  Put them out again last Wednesday same thing again. A few different Tomato plants out but seems to be hitting the big Romas. Anything still in the Conservatory is ok and anything in hanging baskets etc i.e. out of the garden soils is ok. Note all the Romas are in the soil except for the ones in the conservatory. A friend suggest a lack of Nitrogen (I think that™s what she said) so she said I should use a tomato feed. The plants are 3™ high with lots of flowers and some have started to produce toms.  There are some pictures on photo bucket if someone can help?

  THANK YOU JB PS have just feed them with some tomato feed

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