Is reusing compost a good idea?

[Leeds_lad]

I know the nutrients in the old stuff will be used up quickly. Mixing it with home made stuff will be the idea. Is there any reason why this is a bad idea?

Also, is it possible to mix compost used for different stuff in together or is it still a good idea to keep some form of rotation? eg compost that have had tomatoes in this year, don't use it for tomatoes next year etc.

Gets a bit costly buying compost each year to fill my pots that's all

[SarrissUK]

Some would say it does build up disease if you use it over and over, and I don't use it on its own. I do tip all pots that have had something in them together in one bucket, then mix half and half with new compost and use that for when potting stuff on. Like you, it gets expensive, and it doesn't seem to do any harm so far
Having said that, last year I tipped out some of my old compost on the area of the allotment that is a bit damper than the rest, to aerate it a bit.

[Potstubsdustbins]

Providing nothing untoward has happened in the growing season then yes its OK to reuse it. This year I shall be overwintering about 800ltrs (the most ever) in dustbins. It will be riddled and have BFB added before it goes in the bins, the lids will be popped on and there it will sit until next spring.

Some will be used for seed cutting, some mixed with home made compost for potting on and some to top up my spud bins.

What I do in tipping my hat to rotation is mark the bins so I know what was grown in it last and then where possible use it for different purpose's next year.

In twenty odd years I have never had a problem doing this.

Colin

[solway cropper]

Agree with Colin on this. I constantly recycle all my compost but I do ensure that anything that's had potatoes or tomatoes in it goes on the open heap and not in the daleks. That way I avoid most of the risks of disease spread. Next year the toms and spuds will only be grown in compost from the daleks.

I also aim to get two crops from each container every year so I follow heavy feeders like potatoes with salad crops or some other fast grower. You just need to refresh the mix with some BFB or chicken manure pellets.

With 150+ containers I couldn't possibly afford to buy the stuff!!

Colin (another one)

[Feral007]

Yeah I use half and half when I'm repotting plants. And if there is anything that looks a bit suss then I chuck it into one of the many holes that the pup riddles my lawn with. Anti ankle turning mix. I couldn't cope with using new potting mix each time, too expensive and I never have enough anyway since once I start repotting I find several others that need it too.

[Two_Sheds]

The only compost I dispose of is any that's full of fungus gnat larvae or algae (and that goes in the compost bins).
The rest gets chucked back in the bag for reuse (with BFB added to the toms/spud buckets)

[Gearoid]

Yep, I usually reuse my compost for pots. I mix it up with some new and fluff it up, adding a bit of slow release fertiliser.

[SarrissUK]

I'm so glad it's not just me!

[salome2001]

I am feeling like I have cash to burn now because anything from pots gets dumped on the raised beds on the plot to add organic matter... but then with a new plot hacked out of nettles and bindweed, my need for organic matter in them is higher than my worries about buying a few bags of MPC for my tomatoes and peppers

[Florence Fennel]

All the spent tomato compost was dumped in a pile last November and covered with a carpet. I've enriched it with BFB and chicken pellets and I've put three pumpkins in there.

[StephenH]

I should think that the best thing to do with old compost is to chuck it into a compost heap that you're building, because it'll be chock-full of the friendly bacteria that get the hot stage of composting going.

[Moo's Mum]

I used to get through bags and bags of new compost each year, but the last 3 years I've been saving it and mixing it with new. I'd dread to think how much money I've spent/wasted on compost over the years by not reusing it.

[Andromeda]

The only new compost I use is for my seed trays, all the potting on is done with compost from the heap (all the old stuff goes on there along with vegetation etc) and it has manure etc added to improve it.

[jacob]

As above -- I put the contents of all my pots in a big old pile for the winter, then cut it with as much compost as the heap gives me and use again. Only buy compost for seeds...

[VirginVegGrower]

I am feeling like I have cash to burn now because anything from pots gets dumped on the raised beds on the plot to add organic matter... but then with a new plot hacked out of nettles and bindweed, my need for organic matter in them is higher than my worries about buying a few bags of MPC for my tomatoes and peppers

I do the same, it becomes a mulch which in turn adds bulk to my sandy free draining soil .