Polystyrene as drainage

[Bee]

Hi all,
I've been using broken bits of polystrene for drainage at the bottom of pots etc. I do this because:
- I don't have enough stones
- it's light
- it seems a good way of reusing something that's pretty useless
But I was wondering if this could in any way damage my plants. Are there any chemicals that might leak out? (or whatever the technical term is!) I've been growing veg in pots like this - they seem to be doing ok but I thought I should check with you knowledgable self-sufficient-ish-ers.
Thanks!
Sarah

[STHLMgreen]

I had this question as well, so I haven't used it yet but I'm repotting in a few days and it would be good to know.

[ray7]

I have cell type seed trays made from polystrene so some types must be ok.

[ina]

I don't think it's harmful in any way - I've used it before. I've also used corks in the past for drainage. However, exactly because they are light (makes moving pots around easier), the pots are also more esily blown over in a gale - so make sure they are in a position where they can't all topple over!

[hedgewizard]

Don't think that there's anything to leach out, there are no common additives and it's remarkably stable. I've not done it myself as I hate seeing it in the garden afterwards. You're short of stones?

[Millymollymandy]

She might live in a flat or have a small garden. Besides, I remember living with stone free soil in London and when I visited my mum in Somerset or a friend in Bucks I would pick bags of stones to take home with me!! Oh those were the days, now I would love someone to take my stones away!

[ina]

She might live in a flat or have a small garden.

That was exactly the situation where I used it before - I'd turned my two balconies into mini allottments. Large tubs with everything from beans to courgettes to black currants. I was getting a bit worried about the weight of it all...

[Bee]

Thanks for all the advice everyone! Sounds like it's ok to keep on going with the polysterene and it won't poison me after all! I live in a tennament in Glasgow and we have a smallish yard with lots of tarmac and very little soil, so more or less everything is being grown in pots or in raised beds we've built out of old pallets. We used all the stones we could find with our first batch of pots, so now we're looking for alternatives... plus it seems so wasteful to throw polystrene away so I've been collecting it from my department, friends, etc - doing our bit to reduce landfill etc

[Ranter]

I've used polysterene a lot. I live in a small terraced house with a paved back yard, so everything is in pots. I ran out of stones quite early on but never seem to run out of polysterene...