Tomato growing medium

[terrier]

I've just been reading the thread on "Blossom end rot and growbags ". For years I've sat bottomless pots on stones (usually in larger buckets). I feed the pots and water the stones. It's a tried and tested way of growing this type of plant. So my question is why are people using expensive growbags? Just for an experiment this year, I plunged the bottomless pots into plastic bags of horse manure ( Ph about the same as tomato growbags) and the plants are growing just fine without any sign of blossom end rot on the fruits. I would think any moisture retaining medium (i.e. newspaper?) would do the job. So what is the benefit of buying growbags AND using bottomless pots. I'm not trying to teach Gran how to suck eggs here but just a genuine question. Tomatoes grow just fine in growbags without bottomless pots, don't they? All opinions welcome.

[terrier]

[manicscousers]

We do ours on the soil in bottomless pots 3/4 filled with our own compost and topped up with mp compost. A piece of downspout pushed in by the roots, feed the pot, water the pipe. Some of our plants have grown 9' tall this year and are covered in fruit :-)
I think the pots on growbags is to give the plants extra growing space, I always found growbags dried out too quickly in hot weather

[goodlife]

The trouble with growbags is that the roots can only travel down the depth of the bag...couple of inches, and then what?
Yes..with care you can use the growbags on their own and they do work...BUT..you do have ensure that the plants are soooooooooo carefully kept watered and that is the other trouble. They are fine if you have time and energy be all the time there and keep poking and proding to see if the compost and plants need something. But like most people..I do chuck some water..walk away and come back later and see if more is needed (not necessary same day) and by then they might have been needing attention already.
It is so easy to over remedy this gap in care by 'giving just a little bit more water to keep them going for next time......'  =perfect remedy for blossom end rot

So my question is why are people using expensive growbags?

Because they are convenient, lot of people don't know better and particularly 'newbies' for growing think 'that is the way they are supposed to be grown'. Advertising world have done good job getting people trained to use this 'product' and not thinking alternatives.

I did used them few occasions but haven't bought any for years now. Well..I have but not for growing..had bargain lot when garden centre were clearing them out...used the compost in my own mixes

[woppa30]

I fold my growbags in half and then cut them open, that way I have two large, deep bags of compost ready for my toms and cucumbers. I'm no expert, I have only had a greenhouse for just over a year but I must admit this depth of the bag helps with the watering. Once complete and I empty the bag onto the plot the roots, masses of them, go all the way down to the bottom.
My 2p worth,
David

[ancellsfarmer]

Growbags are convenient but you should be able to work out from their contents' appearance as to the likely source of the "compost" that they contain. With the need to create a cheap , marketable product just good enough for the mass market, yet  which are heavy and expensive to transport, what you get is what you pay for.
I would like to  throw to the forum, the suggestion that we consider compiling, testing, and reporting on a recipe(s) for several growing mediums that a typical serious hobby gardener could compile, prepare and utilise fo ra) seedling b) growing on ,and c)  using for a "growing-to harvest" in pots/tubs/containers . The ideal would be like the principle of the old john innes clavering mixes, but with the combination of latterday recyclable materials . Any interest?

[Deb P]

My greenhouse is fully tiled, so my options are more limited.

I've tried using troughs, pots, car boot liners filled with manure, compost and gravel and growbags over the years, and using the growbags topped with my own 'homemade' bottomless pots works best for me. I use B&Q ordinary growbags and use a mix of JI and multipurpose for the pots, three plants to a plumped up growbag. All are cleared in January (usually have fruit going post Christmas, unheated) and the old growbag material put on the flowerbeds. Works for me!

[squeezyjohn]

Growbags work well if you can water and feed on an almost daily basis.  But having gone over to plants in the ground that gets the roots in deep to a nice deep soil ... there's no comparison!  You can leave a tomato alone in all but the driest spell and it will produce for you in the ground ... if you did that with one in a growbag it would just fizzle out and die.

[terrier]

Growbags are convenient but you should be able to work out from their contents' appearance as to the likely source of the "compost" that they contain. With the need to create a cheap , marketable product just good enough for the mass market, yet  which are heavy and expensive to transport, what you get is what you pay for.
I would like to  throw to the forum, the suggestion that we consider compiling, testing, and reporting on a recipe(s) for several growing mediums that a typical serious hobby gardener could compile, prepare and utilise fo ra) seedling b) growing on ,and c)  using for a "growing-to harvest" in pots/tubs/containers . The ideal would be like the principle of the old john innes clavering mixes, but with the combination of latterday recyclable materials . Any interest?

I'm always in the market for saving money, of course, which is why I asked the original question. Do the tomato plants require all the nutrients in a grow bag, after all, the plant sits in a pot of (hopefully) good compost which is fed from an external source, the roots then extend into some sort of reservoir to take up water, so why spend extra money on growbags just to hold water?. May as well just use a bag of earth or sand or whatever you have to hand. At some future date I intend to put my greenhouse onto earth so that I can plant right into the ground but for the moment, the flagstones get in the way.
ancellsfarmer's idea of a database of homemade compost is interesting idea, but I suspect it would be very long and diverse. A quick search on this forum comes up with loads of posts on home made mixes, we just require someone to collate them all  It could take some time. Equally, a simple search on the internet will throw up all the info you require on making your own compost / potting mixes. So far this year, my tom plants are looking happy in bags of horse muck (free), all I need to do now is get them to start ripening