Can I use compost in thermophilic phase in garden bed?

[MatureManure]

Hi all, I have a medium amount of compost that is probably in the thermophilic phase of decomposition (no discernible fruit/veg, but some big clumps of matter, slightly acidic smell) and was wondering the following:

If I throw this compost in the bottom of a raised bed, cover the rest with soil/manure, and leave this for ~2 months, will it then be ok to plant veg seedlings in? Here in Australia it's the beggining of spring, so the the soil should get relatively warm.

Thanks !

 

[oneeye]

Hi all, I have a medium amount of compost that is probably in the thermophilic phase of decomposition (no discernible fruit/veg, but some big clumps of matter, slightly acidic smell) and was wondering the following:

If I throw this compost in the bottom of a raised bed, cover the rest with soil/manure, and leave this for ~2 months, will it then be ok to plant veg seedlings in? Here in Australia it's the beggining of spring, so the the soil should get relatively warm.

Thanks !

Yes, however, I would incorporate the amendment deeply into the ground so it will mix with the native soil.

 

[Owdboggy]

Short answer, yes. We often just dig a trench across the veg patch and fill it with totally undecomposed vegetable material, cover it with soil and plants do not seem to mind. We do get a good crop of 'volunteer' potatoes though! So your partially rotted material would be good to go.

 

[DirtMechanic]

Short answer, yes. We often just dig a trench across the veg patch and fill it with totally undecomposed vegetable material, cover it with soil and plants do not seem to mind. We do get a good crop of 'volunteer' potatoes though! So your partially rotted material would be good to go.

I got butternut squash volunteers doing that this year.

 

[Owdboggy]

Just to add that when I looked this morning there is now no sign at all of the vegetable matter which we buried last Spring. Soil is nice and friable too.

 

[Ernst]

I sure hope you can just till in stuff. I'm at 12 heaping truck loads of grass I mowed free of charge for the neighbors.
If it ain't the right move for prepping a clay-soil bed by tilling in as deeply as possible all the grass I can get then all hope is lost!
The only limit is on oxygen for aerobic vs anaerobic.
I can smell the anaerobic when I till deeply into the compact clay soil at times.
We all like that aerobic soil smell don't we?
And while I am crashing this wedding party ...
What do y'all think of tilling in prilled Urea once the whole bed is level and tilled to depth?
I am playing beat the rain here in Southern Illinois so it's all dry right now.

 

[DirtMechanic]

Nothing about tilling anything in is natural. Hiding trash is not really gardening. If you bury anything deeper than the oxygen layer of a couple inches you risk preserving the goo. Without oxygen the process dies.

 

[Owdboggy]

Not so sure that pure grass cuttings would work just added raw to the soil. By vegetable matter I mean a good mix of stuff, along with grass, vegetable peelings, tree leaves, coffee grounds and tea leaves (not plastic tea bags) etc.
I would let the grass begin to decompose in a turned heap before using it, otherwise there is a real risk of it just doing anything in the soil because of a lack of oxygen.
Composting grass is possible, you just need to keep it watered and aerated, by turning it every week or so.

 

[Meadowlark]

...What do y'all think of tilling in prilled Urea once the whole bed is level and tilled to depth?
I am playing beat the rain here in Southern Illinois so it's all dry right now.

Honestly, not much. As mentioned previously, I prefer to add nitrogen to my garden soil naturally.

How do you know you need it and how much you need? A soil test would certainly help otherwise you are flying blind.

 

[MatureManure]

Thanks for the replies guys! I should've clarified that my beds are essentially 'no dig' - mainly a mixture of potting mix, compost, manure, and some soil dug up from my garden last year. So there's no soil to 'till' the compost into. I actually think I'll let it keep composting for two months and then plant my summer seedlings straight into the compost (sitting on top) if it's ready by then.

 

[Ernst]

Not so sure that pure grass cuttings would work just added raw to the soil. By vegetable matter I mean a good mix of stuff, along with grass, vegetable peelings, tree leaves, coffee grounds and tea leaves (not plastic tea bags) etc.
I would let the grass begin to decompose in a turned heap before using it, otherwise there is a real risk of it just doing anything in the soil because of a lack of oxygen.
Composting grass is possible, you just need to keep it watered and aerated, by turning it every week or so.

The primary benefit I see here is improving the soil tilth. Secondary is some carbon added in and aiding towards the formation of Humus.
On the Tilth side of things, it isn't compacted clay soil anymore.
I figure this is just a place to start. Much more top dressing of organic materials , like you suggest, should happen in the coming years.

 

[Ernst]

Honestly, not much. As mentioned previously, I prefer to add nitrogen to my garden soil naturally.

How do you know you need it and how much you need? A soil test would certainly help otherwise you are flying blind.

Well, according to ChatGPT I need to watch the amount because it will turn to ammonia and evaporate.
The flying blind idea is to provide nitrogen to stimulate the biology before planting anything. A variant of French Intensive perhaps?
Soil test is a goodly thing and I would look into spending the money when it's closer to planting time for Spring-24.
I just wanted to see what folks think. Thanks for your feedback.

 

[Ernst]

Nothing about tilling anything in is natural. Hiding trash is not really gardening. If you bury anything deeper than the oxygen layer of a couple inches you risk preserving the goo. Without oxygen the process dies.

What about those pesky anaerobic microbes!?
I have had the idea that airing out those sour spots was a goodly thing.
From Google:

Anaerobes are bacteria that do not need oxygen and may find it toxic. This group includes very ancient types of bacteria that live inside soil aggregates. Anaerobic bacteria favour wet, poorly drained soils and can produce toxic compounds that can limit root growth and predispose plants to root diseases.

 

[DirtMechanic]

What about those pesky anaerobic microbes!?
I have had the idea that airing out those sour spots was a goodly thing.
From Google:

I cannot fight the soil. I can feed it. Aerobic, or not, mulching soon becomes part of the mix. A very old way of fertilizing is dumping into a large pot or barrel of water. Stinky barrels some people call them. Those go anaerobic, but once dumped out the rotten broken down materials break down even further.

 

[Oliver Buckle]

If you bury anything deeper than the oxygen layer of a couple inches you risk preserving the goo. Without oxygen the process dies.

I dig a trench and fill with anything and everything from compost to fresh veg peelings when I am preparing for planting runner beans. I think what they like about it is the moisture retention, but when I dig next year it is all rotted in fine. Perhaps digging aerates the soil deeper, I had always thought of it as being because the soil contains the appropriate bacteria.
Anyway, I would prefer it to planting in fresh compost, some things might be okay, but it could be a bit much for others.