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Produce => Edible Plants => Topic started by: Robert_Brenchley on December 02, 2016, 10:23:29

Title: Tomato soil
Post by: Robert_Brenchley on December 02, 2016, 10:23:29
How often does the soil in a tomato bed need changing? I've got some large troughs which I could use to grow them, but I'm not looking forward to digging the soil out, and I'm wondering how much I need to do, and how often.
Title: Re: Tomato soil
Post by: ACE on December 02, 2016, 11:48:16
I would think providing you have not had any blighted plants in there it should be good for a few years. The soil is after all just a medium for holding the plant. Loads of chicken pellets and liquid feed next year, perhaps a top dress over winter with some rich dung and it will be ready to go. We have houseplants in pots that keep going in the same old soil year after year until they need repotting all we do is enrich it sometimes with plant food, so if it works for them, why not tomatoes.
Title: Re: Tomato soil
Post by: Robert_Brenchley on December 03, 2016, 18:15:54
I've been told the soil gets poisoned somehow, and has to be changed, but maybe I got it wrong. Blight wouldn't affect the soil, as the fungus is in the tissue itself.
Title: Re: Tomato soil
Post by: ancellsfarmer on December 03, 2016, 21:45:02
Blight is not the only potential problem. Just go to the RHS page on tomato diseases and be scared by the potential pitfalls!!
Sterilizing is difficult, due to constraints of temperature and nonavailability to amateurs of bio-cides, therefore the next option is changing the medium. One-trip containers of your chosen compost, growbags (possibly old compost bags/fertilizer sacks filled with home brew medium), or dig it out and replace. Remember greenhouses and tunnels could be fumigated, spidermite is a frequent issue , viruses and moulds are there as well.
Title: Re: Tomato soil
Post by: Tee Gee on December 03, 2016, 23:49:35
My answer to this question is difficult to answer as I have 4 greenhouses so I an practice rotation.

But thinking about it in terms of how other people go about I would say ring culture is the way to go particularly with tomatoes!

Tomatoes have a unique root system in so far as the top roots are feeding roots and the lower roots are water seeking roots. So if you plant them in a pot/ ring you can use a fresh compost in the ring/ pot and the water roots can seek their moisture in the existing soil below.

This way you only have to change the soil in the pot /  ring !

Otherwise  if you want to grow in the greenhouse border then the answer is change annually.


Title: Re: Tomato soil
Post by: pumpkinlover on December 04, 2016, 08:14:06
I do as Teegee says and for the reason you are asking Robert. It is not just the physical work but the difficulty of doing it in a confined space with out breaking the glass.
Title: Re: Tomato soil
Post by: galina on December 04, 2016, 09:25:33
I partially replace when I have good compost available, but I mostly mulch with really nice compost.  Greenhouses here are in use all year round.  Yes mostly solanum in summer, but at this time of year it is salad stuff, brassica etc.  I also grow carrots, beans and squash occasionally.  It is not quite the monoculture that many greenhouses are.

At the moment I have one greenhouse without winter crops.  Candidate for a better effort at soil replacement.  But in practice that will only mean the top 4 inches or similar, not down to a foot.  If I had problems, I would consider replacing more soil.  Yes Pumpkinlover I also find it difficult to get a fork going in the greenhouse, need to be very careful indeed.  A modified method when the tomatoes need to be planted into slightly tired soil is to make really deep and wide planting holes and refill with a bucket full of decent compost or soil rather than with the dug soil  :wave:
Title: Re: Tomato soil
Post by: ACE on December 04, 2016, 10:37:40
I've been told the soil gets poisoned somehow, and has to be changed, but maybe I got it wrong. Blight wouldn't affect the soil, as the fungus is in the tissue itself.


I have never heard of poisoned soil before just by leaving it, perhaps the feed we put in turns it poisonous over a few years, although the blight is only in the tissue, you would have to be very good gardener to remove every tiny little bit. I rotate my outdoor toms, but still dose the strip with Jeyes before I dig it over for the next crop, just in case. But it is the same soil in those beds year after year. Perhaps indoors with its artificial climate and feeding regime it too intense for continual use.
Title: Re: Tomato soil
Post by: Robert_Brenchley on December 04, 2016, 14:27:49
I'm wondering whether it's a case of toms producing some substance which inhibits root growth. I can't find anything specific though.
Title: Re: Tomato soil
Post by: Tee Gee on December 04, 2016, 16:16:20
So far as I know because you do a lot of high potash feeds to ripen the fruit any surplus salts remain in the soil plus the tomato plants deplete the soil of many other trace elements.

The only way of finding out what is left and what is is depleted requires a soil test to determine what treatment the soil needs to get back in fettle.

The easiest way of doing this is to  'change the soil'

You could take the chance and plant in the same spot again and you might get lucky, then you might not, by which time it is too late to do anything about it!

As I see it; if there are high levels of potash left in the soil this is not a good thing for young plants as they need other minerals e.g. nitrogen & magnesium.

As you all know you not do not apply potash to tomato plants until after the first trust has set, but if it is already there you have the possibility of the plants contracting possibly a physiological problem from which they may or may not recover.

I am no expert on the subject but I guess the reason the common advice to change the soil is the cowards way out to cater for any of the unknowns I have mentioned catching you out the following season.

But as I said;...I am no expert, this is just my point of view!
Title: Re: Tomato soil
Post by: saddad on December 04, 2016, 16:38:52
I do the ring thing, with florists or other buckets with the base cut out... I also grow on alternate sides of the greenhouse/poly beds each year. It has worked well for the last 20+ years.
Title: Re: Tomato soil
Post by: Robert_Brenchley on December 07, 2016, 14:50:45
If you're right about the potash, then growing them to a decent size in a large pot before planting out might get round it. Worth trying anyway.
Title: Re: Tomato soil
Post by: galina on December 17, 2016, 12:08:06
Just a slightly off the wall idea.  Top the soil in your troughs with straw bales and grow the tomatoes in the conditioned bales.  They will rot down but should give you two seasons of good tomatoes.  Silverleaf is very experienced and successful at strawbale gardening.   :wave:
Title: Re: Tomato soil
Post by: galina on December 20, 2016, 12:16:21
just watching Charles Dowding on youtube.  His uses a no-dig system.  And every year he adds 3 inches of compost to his intensive polytunnel and that is it - no fertiliser added and he does close spacing and intensive cropping.  Sounds good and easier than digging soil out and replacing.  I realise that 3 inches is actually quite a lot of compost, but that has worked for him for years. 

https://www.youtube.com/watch?v=QVY4SJt4mzg

 :wave:
Title: Re: Tomato soil
Post by: Robert_Brenchley on December 21, 2016, 16:53:58
Thanks. That gives me an idea how to space the plants
Title: Re: Tomato soil
Post by: Vinlander on January 09, 2017, 11:14:18
The big advantage of a no dig method in my polytunnel would be that I'd not need the extra 3in/75mm of plank in front of the bed to stop soil escaping during digging... the 3in of compost would mostly stay put - even if the bed was already full before it went on (worms use very small shovels).

Unfortunately it becomes essential to maintain a "cordon sanitaire" around the PT to stop couch and bindweed getting in, but I'm working on that anyway - though most people already have that from burying a metre of the cover in a big U.

I have one big problem with 75mm of compost - it's a lot over 15m2 - that's over 1.5m3. It would take every scrap of compost from both the plot and my back garden to get near it. And I'm not prepared to give up using the roughest, dirtiest tussocks in my "anti-fly" builders bags.

Maybe I should start a rumour about why my site doesn't take the free compost offered by the borough - other plots take it and get well over a m3 per person twice a year. There are some counter rumours about 'pyralids but in reality it's a lot safer than any manure in that respect - unless you actually know the cows/horses owners on a regular eye-to-eye basis or better.

Cheers.



Title: Re: Tomato soil
Post by: BarriedaleNick on January 09, 2017, 16:04:33
Tomatoes have a unique root system in so far as the top roots are feeding roots and the lower roots are water seeking roots.

Do you have any references for this?
Don't all roots absorb moisture and whatever nutrients that moisture contains so, for example, if the top roots are in dry soil they are not going to absorb water and therefore nutrients as well..

I have been reading through this http://soilandhealth.org/wp-content/uploads/01aglibrary/010137veg.roots/010137ch26.html
Which is really interesting on how roots can get damaged by transplanting...
Title: Re: Tomato soil
Post by: InfraDig on January 09, 2017, 23:07:23
A really interesting link, thanks very much. A lot to think about! And loads of pointers to where I'm going wrong!!
Title: Re: Tomato soil
Post by: sunloving on January 10, 2017, 07:45:19
I would normally just manure at the end of the year and use the same bed again.
However since I'm getting used to my new poly and the tom bed last year was so blighted I'm moving the toms to the middle bed for hopefully better air circulation.
Can't wait now for the seed sowing bells of February to get a fix of young shoots appearing!
X sunloving
Title: Re: Tomato soil
Post by: sparrow on January 10, 2017, 14:02:02
I was told to top up each year and change the soil to 1 spit down in the greenhouse every 3 years when I asked at the RHS. Reasons were to avoid a build-up of bugs & viruses.
Title: Re: Tomato soil
Post by: hartshay on February 02, 2017, 12:57:10
I remove and replace a spit of soil/compost each year.  Double dig  properly every 2/3 years.  I grow tomatoes densely at about a foot apart and get huge crops in the polytunnel and glasshouses.  By removing soil you eradicate lots of potential pests.  But it is a lot of work!


(My soil is very a sandy/peaty loam that 'eats up' a barrow of compost for every metre each year)
Title: Re: Tomato soil
Post by: galina on February 04, 2017, 18:51:22
Yes, a lot of work, but clearly worthwhile for you.  Gosh that's very tight spacing for tomatoes.  Are you into square foot gardening?  Do you prune them really well too?   :wave:

 
Title: Re: Tomato soil
Post by: hartshay on February 05, 2017, 12:40:15
Yes I do plant densely and also water rarely and never feed!  The plants tend to be vigorous and need lots of shoot nipping and even pruning at times.   I find San Marzano and modern f1 types do best in this regime.   Oh I also underplant with Basil!
Title: Re: Tomato soil
Post by: johhnyco15 on February 05, 2017, 13:15:16
i never grow tomatoes in the greenhouse i have one leanto greenhouse for cucumbers an 8x6 for peppers,aubergines  and a 6x6 for chillis dont have no probs with outdoor toms and i find they taste better than greenhouse grown not sure why thou
Title: Re: Tomato soil
Post by: ruud on February 05, 2017, 16:54:33
I am always put the whole greenhouse under water every two years.If you do that for a couple of hours you flush all the bad things out of the soil.This is for me the only methode that works.Professional gardeners overhere steam the earth.
Title: Re: Tomato soil
Post by: Robert_Brenchley on February 06, 2017, 18:53:43
Interesting. Nature's likely to do that to me every couple of years; the site floods every time we have a thunderstorm in the wrong place.
Title: Re: Tomato soil
Post by: Vinlander on February 09, 2017, 12:35:08
i never grow tomatoes in the greenhouse i have one leanto greenhouse for cucumbers an 8x6 for peppers,aubergines  and a 6x6 for chillis dont have no probs with outdoor toms and i find they taste better than greenhouse grown not sure why thou

I grow very few tomatoes in my polytunnel - some early ones in the soil and some late ones brought in pots.  I always remove them (and beans) June-September inclusive if I've had success raising aubergine plants (tricky buggers).

I prefer the taste of  tomatoes grown outdoors (Gardeners Delight, Sungold, Piccolo), but the main reason is that aubergines & beans are always magnets for spider mite, so I need to spray water on them regularly - which just encourages blight on any tomatoes in there.

I've considered having a smaller, damper tunnel for aubergines within the larger one, but aubergines simply aren't worth that much trouble - you only get a crop when they are dirt cheap in the shops, and even more importantly they taste exactly the same as shop ones. I only do it for the challenge.

Cheers.

PS. Turkish orange aubergines seem to have no real trouble with spider mite - probably because their leaves are as smooth and hairless as a pepper's.