Testing compost?

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Barbara Good
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Testing compost?

Post: # 191457Post lovelygreenleaves »

I read a book recently that said not to use home-made compost as it's likely to be full of diseases and the wrong PH etc. After lovingly making my compost, I'm concerned, is there any way to test it or should I just ignore the book??

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Re: Testing compost?

Post: # 191460Post wildflower »

You can get cheapy PH test kits from most garden stores. Follow the instructions and you should be fine. I'd say, if you're worried, then test it out somewhere small first. Considering how many people have compost bins in their backyards and swear by the magic of homemade compost, I very much doubt you could do serious harm to your garden.
No matter how much we read about how to do it properly, we learn by doing anyway.

Not wanting to offend anyone, but I'm slowly coming to the realisation after reading beginner's organic gardening guides and following advice to only use heirloom seeds because that's what we're all told to do, and mixing the right compost recipes because otherwise my veges won't be any good otherwise, that my vege patch isn't anyone else's but mine.I can use any seeds I like, 100 year old varieties or not, and I can use my own beautiful compost and be proud of having made it. I'm still a n00b, so I'm still going to make mistakes and go through catastrophic failures...but that's the learning curve.
My compost is probably subpar to someone who has been mixing their's for the past decade (or lifetime!). That's experience.
I like to use some heirlooms because they're unusual, but if anyone pulls a face at me for buying my basil seeds from Woolies, then that's their problem.

Not to poo-poo all of the fantastic advice that is out there!...it just makes me a little ticked that no one told me that you need to take it all with a grain of salt.
Apologies for the rant, but that kind of unhelpful, elitist advise that you've read just annoys me.
I'll go focus on my "calm" vibes now :wink:


Living the good life
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Re: Testing compost?

Post: # 191474Post seasidegirl »

I've made some potting and seed compost this year and results so far so good. My first attempt was thrown together because I'd run out, had some seeds to sow, and didn't have a fiver to go buy a bag. The seeds were only hardly annual flowers so I didn't think it would matter much and it didn't.

I just mixed some compost from my own compost bin with some sand from a sack I found in the garden and a bit of soil. I've used the same for potting on some salad seedlings and they are fine too.

I did read somewhere that you can sterilize the soil by putting it in the oven on a low setting for a while. Sounds a bit risky to me, like it might kill good stuff in the soil too so I'm not sure I'd try this.

I've got a grassy area to turn into a bed shortly so I'm planning to save the turf for next year's loam.

My problem this year is that because I'm planning to mulch as much as possible I'm not going to have so much going into my compost bin. Eg grass cuttings will go straight on as mulch.

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Re: Testing compost?

Post: # 191484Post theabsinthefairy »

Wildflower - I agree that sometimes the tone of advice being proffered in books and on line etc can be a little disheartening as it all seems to be telling you that you MUST do things in a specific way for it to be a success. Luckily I have never been one to listen to voices of authority and obey instantly (my poor teachers) but it can be difficult to find the kernels of wisdom and adapt them to your specific abilities, environment etc.
seasidegirl wrote:and didn't have a fiver to go buy a bag

I make my own compost for seedlings and have expermented with various things, the following being the most recent:

Recipe 1 - for bigger seeds - last autumns leaves collected and left in a bag to mulch down over winter, then mixed in with some compost from the bottom of my compost bin, which includes chicken poo, and then some mole hill dirt

Recipe 2 - some of the veggie plot covered in rabbit cage shovellings straw and all and left for the winter to break down - this has given a thick rich smelling black compost that crumles up very lightly and so I have been using this for the smaller seeds like toms and peppers

I don't sterilise the earth - I understand that a lot of people who use mole hill dirt sterilise it first in the micro wave - :scratch:
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Living the good life
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Re: Testing compost?

Post: # 191524Post Marc »

The main problem with making your own is usually weed seeds. I did have an old microwave in the shed that I used to sterilize the soil etc. You need a cooking or similar thermometer to avoid overheating it. I think it wants to get to about 80-90 degrees C. I'm sure you could find the right temp on the web. My father always did his in the oven of the Rayburn.
I found mine worked very well, must get back to making some when I have time. John Innes compost is made with heat sterilized soil and that's fine too.
Only two things are infinite, the universe and human stupidity, and I’m not sure about the former.

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Re: Testing compost?

Post: # 191536Post grahamhobbs »

Why should your compost be full of deseases and the wrong PH?

Well I doubt if there are many gardeners that would put deseased material into their own compost, so where are all these deseases going to come from - the air? Well if they are in the air, they are everywhere.

The wrong PH, why would it be the wrong PH, unless you put loads of meat on your compost and its an anaerobic mess.

No as has been said, the problem with homemade compost is that it often doesn't reach temperatures to kill weed seeds. If you don't want weed seeds in your compost, the solution is try not to put them in there in the first place. In fact, try not to let your weeds go to seed on your plot in the first place, but if they have, seperate them and put them (or just the seed or flower part) in a barrel of water, that will kill anything after a while, including the roots of bindweed.

If you want to make sure your compost reaches high temperatures to kill any seeds, then it either means lots of work turning the compost (unless you have a rotary type - my brother in law has made a great own from one of theose food quality blue drums and a scaffold pole) or add loads of horse manure.

So go ahead and use your own compost, if you think it might have lots of weed seeds in it, just use it in places where it is not critical or is buried.

I'd suggest to everyone to also start a wormery and use this worm compost, together with leaf mould and sharp sand, for raising your own seedlings in, as this can be totally free of weed seeds.

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