Smallest pot for tomatoes

Last year I grew tomatoes in buckets and had to use quite a lot of compost etc as a result. I saw on tv recently a large greenhouse with really tall tomato plants and they had grwon from what I thought looked a small pot.
For tomatoes grown in a small greenhouse ( height wise) what is the smallest size container that one plant when mature will be happy in ?

 

Mine get on fine in 12" pots, Louise.

 

I would have thought 9" diameter, and about a foot tall.

The smaller it is the more often you will have to water. When I had mine in pots at the height of Summer I had to water at lunchtime as well as the morning, so if you are out-to-work that might be a consideration.

Does it make that much difference to cost though? A 75L bag of multi-purpose is about £4 and I reckon that will do 3 plants, maybe 4. Grow bag would be about the same. So its about a pound-a-pot. Reducing the pot size is only going to shave 10 or 20p off that cost, but I think it likely that it will cost more than 20p in lost yield as the plants will be more stressed.

You might save more by shopping around for Tomato Fetrilizer. For example Tomarite is hugely more expensive than "own brand" stuff, which I think is just as good.

I grow mine in the greenhouse border (not an option if you have slabs / concrete floor, obviously). Much less hassle with watering (and more floor-to-ceiling height too). But I do change the soil each year (I use the compost heap, so its not a particularly heavy task, compared to barrows of soil, but "heavy" is a relative term of course)