[Kirpi]

I understand that bought in compost for large containers is pretty much spent once plants like tomatoes, potatoes, peppers etc have done their season.

But I wondered about keeping costs down by using the same compost to grow much less demanding veggies the following year; like carrots. Then I guess the two year old compost is only fit for use as a soil conditioner.

Any views?

[Beetroot queen]

I was wondering what to do with my compost from the carrot containers so will be interested to know. I was going to add it to the compost heap if not re-using it.  always just used it to top up beds before.

[GreyScales]

I used the compost from last years crop to grow onions over winter, which we're enjoying now. Just mixed in some onion feed and threw some sets/spring onions in. Better than throwing the compost and leaving the containers empty all winter

[Beetroot queen]

I was wondering what to do with my compost from the carrot containers so will be interested to know. I was going to add it to the compost heap if not re-using it.  always just used it to top up beds before.

That wasnt meant to be a grumpy face just a  one.

[LilacSandy]

You could try using it for lettuce as that does not need too much but to be honest I would always add to the compost heap, it is not worth risking any overwintering diseases that may have built up.

[Steveharford]

Kirpi. I have come to the conclusion that bought compost in its 'as bought' state is only good for soil conditioning to start with. Borne out by the fact that my mother on law never pinches out her tomato side shoots whereas I do , yet her tomatoes ( my spares) are doing a hell of a lot better than mine, and I think it is because she has been feeding them with miracle gro since the day they were potted on, where I have been relying on the compost having enough nutrients to do its job. Both of us had the same compost. Lesson learnt I think.

[Madame Cholet]

I use my spent compost to top up large tubs at home.

[BigPaddy]

I use last year's compost in buckets with blood, fish and bone added for early spuds in the greenhouse. Similarly with outdoor tomatoes. I probably have chillis, peppers and aubergines indoors in it too.

My thoughts are that it is only a source of nutrients in itself for a few weeks, after that it is just a growing medium. I need a growing medium so I reuse it and add fertiliser. The BFB just gives plants a start then I generally use tomato feed for everything.

I do try to avoid as far as possible using the compost for the same plants each year, but I'm not over zealous about that.

Third year it is soild conditioner only.

BP

[mjpalin]

I'm with the add it to the compost heap group, helps to add bulk to the heap.

[chickpeacurry]

I was also wondering what to do with the old grow bags and soil in the big black buckets.   Could disease survive in the soil if compost.  Could add it to the flower areas.  Could it be used to top up needs with crops like leeks. 

[Yorkie]

Some diseases will persist in the soil, but it's also about nutrient depletion.

That's why I wouldn't use it for the same crop family.

[baldy-bob]

I use some of mine for potting up my over-wintering strawberry runners, anything left over goes on top of my beds in the Autumn.

[AnnieB]

Owing to the fact that I tend to leave a container full of compost doing nothing over a winter after I have grown something in it I have noticed that when I empty it out it looks darker, richer and generally better then when I originally put it in the container. 

Usually it ends up on the soil to add to the structure, keep things easy to dig and builds up the level lowly, also 3 bags of compost are about right and this is usually what is on offer. Have once or twice added half a bag of manure and reused some, usually with good results.

[GreyScales]

Question. If you use depleted compost as a soil conditioner, aren't you spreading all the build up 'problems' in that mix over your growing area? Like if you grew tomatoes in compost one year and then dug it in your beds, would you be able to grow tomatoes in those beds next year?

I don't have a lottie yet so I'm unsure about many things. I heard pests and such can accumulate in a growing medium if you plant the same crop variety in the same place, so wouldn't you be technically adding those pests to your beds from the compost?

[Kirpi]

I think you have a point. I wouldn't tip spent tomato compost onto the next year's tomato or potato bed for this reason, but would use it for carrots, lettude I think the next year and then put it on the beds for roots, onions, beans etc. the third year as a soil improver.