Recycling potting compost?

chookie1

Am I OK in chucking potting compost on my compost heap at the end of the year when my tomato plants and so on have finished? Obviously there aren't many nutrients left in it, but I figure it's a good "medium" to add to the mix. This compost then goes on mulching beds and the like.

What I'm vaguely worried about is plant diseases persisting but I presume that there's little risk if it's only used once.

Can anyone reassure me - or indeed tell me I'm completely wrong?

Cheers!

forgotmyname

I have been reading its not a good idea to put potato and tomato plants on the compost pile.

May have traces of blight you dont want to spread on later.

Lotus-eater

chookie1 wrote: »

Am I OK in chucking potting compost on my compost heap at the end of the year when my tomato plants and so on have finished? Obviously there aren't many nutrients left in it, but I figure it's a good "medium" to add to the mix. This compost then goes on mulching beds and the like.

What I'm vaguely worried about is plant diseases persisting but I presume that there's little risk if it's only used once.

Can anyone reassure me - or indeed tell me I'm completely wrong?

Cheers!

Well lets put it this way, when you grow tomatoes in the soil, do you dig it all up at the end of the year and take it down to the tip?

You don't? :eek:


So, the compost you use in pots you treat the same as your garden soil, don't grow the same family of veg in there the next year and reuse it. You have to replenish the store of nutrients in it, which tbh is best done by just mixing it up in a bed of soil and then treating the bed as you normally would.
You can add fertiliser to it and reuse it in pots and that can work fine as far as I know, I try not to grow in pots as compost costs alot or I grow in a mix of compost and topsoil.

Filey

Most of my plants (and trees) are grown in containers. As Lotus eater said, compost costs a lot, so when I have plants which are not perennial I tip all the compost together, add FBB, sometimes a bit of lime according to my mood, some well rotted horse manure or soil conditioner, and later when I am re-potting that's what I use. Only been doing this for a couple of years but so far no problems.

Davesnave

I recycle a lot of potting compost by microwaving it to get rid of weed seeds. As I now have the microwave (it's a biggie!) on a separate meter, I can monitor what it's costing me. So far, it's good.

....And before some kind person comes on to tell me that I'm blasting all the 'good' organisms to death along with the weeds, I know that. I don't use the recycled stuff 'neat.'

misskool

I have rock hard clay soil so after growing the first hungry crop followed by a couple of salad crops the final mix gets dug into the ground.

alanobrien

Been using recycled compost for years, all i do is add a scoop of blood fish and bone then use it wherever its needed.

stilernin

I only take out the top 1/3 of compost from the large containers I use for veggies. I mix a bit of blood fish and bone into the bottom 2/3 and top up with fresh compost.

What do I do with the 1/3s that come off the top? Well I find more containers of course :rotfl::rotfl::rotfl::rotfl:

Is there a mathematician amongst us who can say how many times I can do this before I fill the garden? (A bit like the "how many times can a waterlily increase by 1/2 before filling the pond" question)

Primrose

As long as any tomatoes or potatoes grown in potting compost don't have blight, it's OK to recycle it onto your heap. I sometimes use old potting compost from my pepper, chilli and aubergine plants to fill in dips in our lawn. (All other vegs, including tomatoes, I grow direct in the soil). On one occasion I tipped it all my spent compost into a large empty potato growing sack and throughout the year mixed in many of my kitchen peelings and some grass cuttings, allowing them to rot down. (which they did perfectly as the container was kept in a sunny position where the heat rotted everything down very quickly). The following year this gave me a lovely large container of freshly nourished compost to start off the sowing and potting process all over again. If I'm using this for a second year, I throw in a handful of chicken manure pellets. I'm very careful about not putting any diseased plant material into old compost or on my compost heap and so far have never had any problems.

Lotus-eater

Primrose wrote: »

As long as any tomatoes or potatoes grown in potting compost don't have blight, it's OK to recycle it onto your heap.

Are you saying that if you have blight, you have to throw away the compost?

Primrose

Lotus -eater - A couple of years when my tomatoes were blighted I disposed of all the haulms in a bin bag in my rubbish and kept them well away from the compost heap, although they were grown in a border, and not in compost. If I had any used compost which came from plants in pots which had suffered blight I'd keep it away from my vegetables and probably use it for topping up dents in the lawn or flower borders where vegetables weren't grown. There seems to be an contrary argument about whether blight spores remain in soil/compost. . One year I lost every single outdoor soil-planted tomato from blight. The following year I grew tomatoes again in the same location and suffered no problems. I normally grow climbing beans and tomatoes in a long border against a fence and alternate their positions ever year to try and protect against diseases, but that year I forgot which way round I'd planted them and put beans & tomatoes in the same spot again. Despite the overwhelming blight the previous year, the tomatoes prospered, so I suspect blight infection is really about weather conditions during the year in progress more than the disease lingering in the soil.