Tomatos By ring culture

Hello everyone.
I'm new to gardening and would like some advice, I'd like to grow tomatos by ring culture, by greehouse has a concret floor and I've read that if I fill the area with builders ballas I'll be able to grow them on the ballas
My question is can I use limestone chippings for the ballas it appears to be the cheapest aggregate unless you members know better, I'd appreciate any information.
Thank you

tibbar wrote: ...
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chipped limestone will have very high pH.
songbird

'songbird[_2_ Wrote: > ;954136']tibbar wrote:
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Thanks Songbird for your reply, does having a high pH make them unsatistactory for growing tomatoes?

tibbar wrote:
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High pH in soil will reduce the absorbtion of some minerals which become less soluble. Most veges (this is a generalisation) like it about 6-6.5 that is slightly acid and IIRC tomatoes are in that group. The question that I cannot answer with certainty is will limestone chips in the aggregate layer have the effect of raising pH too high. I am guessing there will not be very much effect in the time that tomatoes grow as limestone chips will not dissolve readily.
I take it that there is water in the aggregate layer. If so test its pH and you will know and nobody needs to guess. A dye indicator pH test kit is cheap and accurate enough for the purpose and will always be useful if you are going to grow veges.
David

David Hare-Scott wrote:
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freshly chipped limestone will be quite different from aged limestone. in between there will be rinsed limestone.
i wouldn't consider any of them optimal. for a few dollars more there are better substrates that you won't have to fight continually to keep the pH in range. so sure it might cost less to start, but then you pay later.
the hydroponics poster here often is Gunner. i'm a dirt gardener with much experience with crushed limestone because we have around a hundred tons of it here and i've studied it in various circumstances as a result over the past 15 years.
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note David that the OP is starting from scratch. with new chipped limestone which is a harsh substance. even with a lot of rinsing it takes quite a while to mellow.
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*nods* i'd certainly use something else if it is available.
songbird

'songbird[_2_ Wrote: > ;954303']David Hare-Scott wrote:-
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Thanks Gentlemen your advice has been very much appreciated. Tibbar

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PH aside, this strikes me as a very dumb idea. I presume you've read the Royal Horticultural Society's suggestions for Ring Culture. <http://apps.rhs.org.uk/advicesearch/Profile.aspx?pidC7
They basically say that the Family: Solanaceae is best for this technique, but they never recommend it. You will have to water 2 to 3 times a week and there is nothing to hold the nutrients, so you may need to fertilize with each watering. This isn't like hydroponics where you can recycle the nutrient solution. With Ring Culture you add your nutrients, and then it is gone. Washed away with the following watering, if nothing else. That's lots of money down the drain.
My suggestion is that either you go hydroponic, or plant in pots with potting soil (which will hold the added nutrients).
If you insist on doing Ring Culture, do it right, not on the cheap. I presume gravel is what you would need.

Derald wrote: ...
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it has a cute name...
songbird

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Thank you, Mr. Missy ;O)

Derald wrote:
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ok, i went and looked at the webpage and the first paragraph did contain some of the "Why"s...

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And what I read was that the aggregate had to be sterilzed after each crop (season) to avoid transmitting root diseases. Heat or chemicals that will set you back, when with hydroponics you could simply recycle a sterilizing solution, or use crop rotation with conventional agriculture. If you just want to keep it damp, that's called a hose.

Prepare the aggregate bed a couple of weeks before planting young tomatoes and other crops into their positions in April. Try using gravel, hydroleca or perlite as your aggregate.
Thoroughly clean the growing area to avoid the aggregate becoming contaminated with debris from preceding crops or infected soil. Make a trough or dig a trench to contain the bed of aggregate. The minimum depth is 15cm (6in), but no more than 25cm (10in) is usually used. Prevent soil from contaminating the aggregate by lining the trough, trench or floor with thick polythene with drainage holes every meter. The aggregate bed needs draining, as standing water will harm plants. Waterproof troughs are possible but need careful managing to avoid root problems.
The bed should be made far enough in advance of setting out the plants for it to warm up – two weeks should be sufficient. Fill bottomless containers, (25cm (10in) diameter, 30cm (12in) tall) with growing media (that used in growbags is ideal) and plant young plants in April. Special pots of bituminous paper are available for this purpose, but you can use any container that is open at the base. Leave the newly potted plants on the greenhouse floor, not the aggregate. As the plants grow, space them out so that the leaves of neighboring plants never touch. This will avoid leggy growth.
Once established, when the roots are showing at the bottom of the pot, place the pots on the aggregate with a close, firm contact between compost and aggregate. Spacing is the normal distance for indoor crops. Keep the aggregate moist and water the pots two or three times a week adding liquid fertilizer if growth is pale or insufficient. The tomatoes are then grown in the usual way. After the crop is finished, remove the aerial parts of the plant and ease the roots out of the aggregate and discard.
Clean and disinfect the aggregate after clearing the crop. The material can be used for many years unless problems arise. To avoid polluting watercourses and ground water, aggregate should not be cleansed in situ, but lifted, washed and the disinfectant solution safely disposed of, according to the manufacturers' instructions.