How best to treat these potbound tomatoes

[Primrose]

Have got about 2 dozen tomatoe plants which are becoming potbound with roots coming through bottom of pots. They really really need planting outdoors but it's just too cold yet. How best can I keep them going without being retarded until the weather warms up?

Will feeding them with a regular dose of Tomorite fit the bill? If so, how often should I be applying it? Is there anything else I can do? I don't really want to have to repot them all although I realise the roots should really have room for expansion.

[Monika]

I wouldn't give them Tomorite, Primrose, unless they are already forming fruit. Could you not pot them into larger pots until they can go outside? It wouldn't have to be solid pots, those made of thin plastic/"tarred" paper would do or perhaps even plastic bags larger than the current pots? Supermarkets often give away those tall black pots in which they display their cut flowers, perhaps you could get some of these? You would, of course, have to buy in a fairish amount of compost to fill them, I'm afraid.

I hope it gets warmer soon so that they can go straight outside!

[oldherbaceous]

Dear Primrose, tomatoes are one plant that do seem to be able to recover very well from being stressed at a young age.
But i think a more general plant food would be better really.

Another thought, but i'm not sure how well it would work though, would be to put them close together into a cardboard box, just a little deeper than the top of the pots, and try and top dress them with more compost, if you can see what i'm trying to get at.

[Geoff]

What size are they in?
Won't come to any harm in 4" or bigger, 3½" probably OK, anything smaller I think I would look at potting on at least some of them. Pot bound starved plants often fruit earlier but perhaps ultimately not as prolifically.

[Primrose]

They're in 3.5" pots so not much room for manoeuvre. I will probably have to repot a few of the tallest just to be on the safe side. I'm just running out of indoor & mini plastic greenhouse space to accommodate everything!

[FelixLeiter]

Roots coming out of the bottom of the pot does not necessarily indicate that they are root bound. Do they dry out too quickly? Are they showing signs of stress (dropping leaves, becoming discoloured, for instance)? These are the signs of being pot bound. A 3.5" pot is quite small for raising tomatoes in. I get mine into 5" pots as the final size before planting them out, so pot them on, I would. And feed them.

[Colin Miles]

I would certainly repot them and try putting them outside somewhere sheltered during the day and bring them in during the evening. Repotting will result in a better root system - may slow them down a bit - but far better results in the end.

[Myrkk]

This is a problem I'm having at the moment, mine are in 3" pots though. Will have to get them potted on tomorrow I think.

Space is always a nightmare at this time of year. Can't wait until my garden is fixed and I can get a greenhouse sorted out.