tomatoes

Is it possible Peppertom that you are overwatering (also the same problem with your cucumber perhaps>)

It could be a scorch caused by too strong a feed.
At the start of the season, half feed strength is fine.

Mr TK

Are the plants forming fruits? If not, then they don't really need feeding. Overfeeding can cause as many problems as underfeeding, so just follow the instructions on the feed container.
And as Sanjo says, they might not need so much water, unless they're actually drying out in that time. Do you water morning or evening? If it's in the evening, then they 'sit' in cold wet soil all night, so better in the morning if you can.

I get this every year.

I've got it now on 4 of my tomato plants stacked up in the greenhouse.

This year it is on the variety Stupice but they are not all affected. They are not even next to each other,

Last year it was on some of my Gardener's Delight.

I've had it for years and years.

It normally happens in the first few weeks after being transferred to their final pots in new compost. It only affects the lower leaves.

Last year I used grow-bag compost in my pots (buckets) - this year I've used B&Q multi-purpose; same thing happened both time.

The buckets all get the same watering in (not a lot!!!) and are still moist from that watering (ie not watered again) by the time the yellow mottling starts.

I tried Epsom Salts last year; in previous years I've fed them early. They stay as they are.

I've come to the conclusion that, since my greenhouse is shaded by a giant oak tree they do not get enough light and are taking chlorophyll from the lower leaves to supplement the new growth.

I think it may be that the affected plants were in better light before being put into their final position but I haven't done a trial to prove it.

I've stopped worrying about it.

All the plants have grown fine and given an abundance of tomatoes.

I don't think it is anything serious so don't over-water (you will wash nutrients out of the soil if water gushes out of the bottom of the pot and if the roots are stood in saturated soil they will not have the air they need to grow and will rot), don't feed until the first tomatoes have formed and maybe remove some shading on cloudy day and I think you'll be Ok.

Thanks for your responses

they have helped :-)

the usual reason that the leaf colour changes is a build up of certain chemicals,just get some epsom salts and dilute one tablespoon in a bucket of water and drench the plants once a week til colour comes back...been doing it years(its cheap and it works)...and it wont add any taste or taint to the toms...