Growing tomatoes in grow bags

[StrawberryPot]

How does it work? The crosses for cutting the bags suggest they're meant to be laid flat. But surely that doesn't give enough soil depth for the tomato plant roots? (Google tells me 12" minimum) Or enough to support canes.

But if you stand the bag on end, surely that's an unnecessary amount of soil depth for the roots. Could anyone advise please?

I cut the bottom out of the pot and then stand it in the grow bag.

Why not just leave it in the pot? What's the advantage of standing the pot in a grow bag?

Monty Don cuts his Grow Bags in half and stands them up on end.

Monty Don cuts his Grow Bags in half and stands them up on end.

Now that's a great idea!

There was an item on last week's Gardener's World showing good three techniques, including the 'cut in half stand on end' referred to above.

How do you cut it in half without everything spilling out?! I struggle enough opening an ordinary bag of compost at the top! 😁

We grow them flat.
Support canes form a triangle rather than straight up.

Ha, interestingly they glossed over that bit on GW!

But it looked like it was laid flat then cut iwth a sharp knife, then each half stood up. I guess any compost that falls out can be put back in.

We grow them flat. Always good quality bags- made the mistake of cheap ones one year and it was a disaster. When we plant them up we bury a horizontal stick with a vertical string attached which is tied up to the top of the green house and train them up that. You need to use nylon twine or it rots.

There's usually a decent amount of space in the bag so just kind of fold it in half, shake the soil so half is in one end the other half in the other end and cut down the middle.

These are our currently very happy tomatoes…grown in the grow bag lying flat.

@DelurkingAJ - how many plants have you got in there? They do look healthy.

I've tipped the contents of a growbag into a now redundant recycling box. (The council suggested using them for other things when delivering a new wheely bin for plastics, tins and bottles).
But usually I just lay the bag flat and plant them in it as is.

I cut mine in half, have done ever since I saw Monty Don doing it! I roll and punch the bags around to loosen the compost, as it gets compacted when they’re laid flat in the garden centre. Then I sort of stand them up in an inverted V and cut the plastic across the top to make two separate bags of compost.

It does mean you’re being a bit extravagant with the bags but the plants get a lovely deep root-run.

@Halsall - do you make drainage holes?

@StrawberryPot The bags I get seem to have small holes in anyway so I don’t, no. Never had any problems and I get a good crop. I use these metal holders as well, if you imagine an individual half-growbag in each. The cane threads through the top and keeps it nicely stable.

@StrawberryPot we’ve got six plants in there…two for each hole in the bag.

@DelurkingAJ - 6! That's encouraging! I've grown a lot of tomato plants from seed and was thinking I would need to spend a small fortune on containers/grow bags.

I bought some new bags this year that you cut along the long edge. Can only fit two in but I find grow bags not deep enough

The roots spread into the growbag. With bottom cut out of the pot they can spread easily