Author Topic: Do I need to change all the compost?  (Read 3803 times)

Malcolm

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Do I need to change all the compost?
« on: April 18, 2009, 18:32:46 »
Hi - first post, so I'll admit that I don't actually having an allotment (waiting 3 years) - I have a lot of large-containers on my patio. Last year they weren't edibles, and I had to dose them all for vine weevil, which stopped the weevils but sadly didn't protect the plants from the cold. Can I use the same containers/compost for growing vegetables this year or do have to throw it all out and start again? Thiachloropid is only effective for six weeks but I don't know if it's broken down safely and is now suitable for veg-growing.

caroline7758

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Re: Do I need to change all the compost?
« Reply #1 on: April 18, 2009, 18:34:23 »
Hi,Malcolm. Sorry, I don't know the answer to your question, but welcome to the site!

manicscousers

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Re: Do I need to change all the compost?
« Reply #2 on: April 18, 2009, 18:38:28 »
Hiya, malcolm, welcome to the site  ;D
lots of people on here with garden plots or container growing..can't help with the question though  :)

tonybloke

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Re: Do I need to change all the compost?
« Reply #3 on: April 18, 2009, 19:05:59 »
The chemical affects insects, not plants. yes you will be O.K. to plant veg this year. ;)
welcome 2 the site as well !!
You couldn't make it up!

Malcolm

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Re: Do I need to change all the compost?
« Reply #4 on: April 18, 2009, 19:14:09 »
The chemical affects insects, not plants. yes you will be O.K. to plant veg this year. ;)
welcome 2 the site as well !!

It's not the plants I'm worried about, it's ME !!!  The bottle says "do not use drench on edible plants" and "contact local authority for disposal details" so I don't want to grow a nice salad in the summer only to find it's all toxic  :(

Baccy Man

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Re: Do I need to change all the compost?
« Reply #5 on: April 19, 2009, 01:26:12 »
Thiachloropid is only effective for six weeks but I don't know if it's broken down safely and is now suitable for veg-growing.

I assume you mean thiacloprid, research carried out for the Food and Agriculture Organization of the United Nations included a section on uptake by rotational crops. 3 successional crops were planted 30, 170 & 354 days after the thiacloprid had been applied all 3 crops absorbed thiacloprid. Since most of the metabolites detected in the plants were either soil metabolites or their derivatives, it was concluded that the residues in the rotational crops resulted from uptake of soil metabolites which remained stable in the plants or to some degree were further metabolised by the plant.
The full 177 page report can be found here.
ftp://ftp.fao.org/docrep/fao/010/a1127e/a1127e12.pdf

Thiacloprid will eventually disappear but it will take over a year to do so not 6 weeks.

A second point to consider is the nutrients in the compost unless you filled the pots with terra preta they the soil is not going to regenerate it would need to be partially replaced & fed at the very least.

grannyjanny

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Re: Do I need to change all the compost?
« Reply #6 on: April 19, 2009, 08:14:11 »
As compost only has nutrients for 6 weeks then you have to feed I would think the compost is ready to be replaced. Personally I wouldn't risk it & would give the pots a good clean as well. Good luck with your veg growing, what are you thinking of growing?
Janet

Malcolm

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Re: Do I need to change all the compost?
« Reply #7 on: April 19, 2009, 08:39:10 »
Thiacloprid will eventually disappear but it will take over a year to do so not 6 weeks.

Thanks. I'd found a different review which gave different timings for various crops but over a year for just grain crops. Whatever, its classification as a neurotoxin and the recommendation of application with full respirator and body suit etc spooked me yesterday so I decided that I'd change it anyway. Makes sense anyway, because if there are any vine weevil grubs left in the compost it gets rid of them as well.

Going to trash my car's suspension taking all that to the dump!

tonybloke

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Re: Do I need to change all the compost?
« Reply #8 on: April 19, 2009, 08:49:04 »
makes you wonder why they are allowed to sell this stuff, don't it??
You couldn't make it up!

Malcolm

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Re: Do I need to change all the compost?
« Reply #9 on: April 19, 2009, 08:50:34 »
Good luck with your veg growing, what are you thinking of growing?
Janet

I have so little room and an East facing garden so I'm just growing tumbling tomatoes in baskets out the front (v.quiet road), and out the back tomatoes, three different types of courgettes, and strips of lettuce, beetroot, onions and mustard//muzuna/perpetual spinach. The most spacially-challenged veg garden ever!

Malcolm

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Re: Do I need to change all the compost?
« Reply #10 on: April 19, 2009, 08:54:54 »
makes you wonder why they are allowed to sell this stuff, don't it??
Hi Tony - it makes me worry about people who DON'T read the labels!
Where has this wind come from? - I can hear my my rooftiles lifting it's so strong.

grannyjanny

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Re: Do I need to change all the compost?
« Reply #11 on: April 19, 2009, 09:15:46 »
There are lots of dwarf veg for growing in pots. I think T&M do a collection. Hestia dwarf runner beans, but you can grow runners & french beans  in a pot, there's a small cauliflower. Do you have a large family, 3 courgettes is a lot.
Janet

reddyreddy

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Re: Do I need to change all the compost?
« Reply #12 on: April 19, 2009, 09:22:19 »
There's a good biological treatment for vine weevil (nemasys) so if you get them again I would use that as nit's 100% safe.

saddad

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Re: Do I need to change all the compost?
« Reply #13 on: April 19, 2009, 09:47:12 »
I'd agree with the biological control.... have you any border soil you can spread the compost on? Just to save the poor suspension... can use it as a top mulch or lawn you couls spread it on, the birds would soon pick out any remaining grubs...  :-\

Malcolm

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Re: Do I need to change all the compost?
« Reply #14 on: April 19, 2009, 10:03:35 »
There are lots of dwarf veg for growing in pots. I think T&M do a collection. ... Do you have a large family, 3 courgettes is a lot.
Janet

(Back from filling up the basket towers with compost and water-gel. Now it's cold and cloudy - they really got it wrong today).
I looked at the dwarfs (dwarves?) but thought they wouldn't provide much return for the time and space taken.
The three courgettes is so I can can find out which is the best for here (South Downs, windy and dry) and because I wanted the Zucchini for crop and the yellow ones for looks - with a garden just 20 x 20 it has to be a pleasant place to sit and mark books after work. The front one's about the same size and mainly laid to lawn - I thought about shocking the neighbours, digging it up and laying out beds but decided against it.

I'll figure out how to put photos on the Gallery to save my lengthy explanations.

Malcolm

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Re: Do I need to change all the compost?
« Reply #15 on: April 19, 2009, 11:35:15 »
I'll figure out how to put photos on the Gallery to save my lengthy explanations.

There you are -  I couldn't find how to add an avatar but I've got better things to do now. You can see how small (and dark) the garden is. In case you're wondering why I paved it over, it's because my first attempt at growing veg revealed that when they built the houses, they put all the waste rubble in the back, put two inches of soil on it and called it a garden.

tonybloke

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Re: Do I need to change all the compost?
« Reply #16 on: April 19, 2009, 14:15:04 »
I'll figure out how to put photos on the Gallery to save my lengthy explanations.

There you are -  I couldn't find how to add an avatar but I've got better things to do now. You can see how small (and dark) the garden is. In case you're wondering why I paved it over, it's because my first attempt at growing veg revealed that when they built the houses, they put all the waste rubble in the back, put two inches of soil on it and called it a garden.
ahh, the pleasures of buying a newly built house!!
You couldn't make it up!

 

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