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Growing in a pot of straight compost

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Growing in a pot of straight compost

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Hello,

Im a first time grower and i’ve decided to plant my auto seeds in pot filled with just compost. (westland with john innes multi-purpose) It’s quite a clumpy medium as it contains wood-chip.

Im wondering if this medium will be okay to grow in?

Any advice/info/tips would be greatly appreciated.
 
Hello,

Im a first time grower and i’ve decided to plant my auto seeds in pot filled with just compost. (westland with john innes multi-purpose) It’s quite a clumpy medium as it contains wood-chip.

Im wondering if this medium will be okay to grow in?

Any advice/info/tips would be greatly appreciated.

It's likely just going to be way too "hot" to sustain it, and without anything to help aerate the soil the roots won't get enough oxygen. What you can expect is it will pop from the dirt, grow a node or two, then wilt and die.

Even with soil, you're really giving them a latticing structure with nutrients embedded. What you dropped them into is a latticing structure made almost entirely up of nutrients. So you want to put some structure together like with coco/peat/perlite/etc. and then your compost can sit in it providing a steady source of nutrients, in a concentration that isn't too high for the plant, and enough aeration so the roots can breathe right while they're eating. If you're just starting out it's easier to just buy a shelf blend but if you'd like help whipping up a blend with what you've to to work with that won't be too hot for the plant, just say the word.
 
It's likely just going to be way too "hot" to sustain it, and without anything to help aerate the soil the roots won't get enough oxygen. What you can expect is it will pop from the dirt, grow a node or two, then wilt and die.

Even with soil, you're really giving them a latticing structure with nutrients embedded. What you dropped them into is a latticing structure made almost entirely up of nutrients. So you want to put some structure together like with coco/peat/perlite/etc. and then your compost can sit in it providing a steady source of nutrients, in a concentration that isn't too high for the plant, and enough aeration so the roots can breathe right while they're eating. If you're just starting out it's easier to just buy a shelf blend but if you'd like help whipping up a blend with what you've to to work with that won't be too hot for the plant, just say the word.
Thanks for your reply!

Could you recommend me some shelf blends and also whipping a blend up with what I have to work with please?
 
Thanks for your reply!

Could you recommend me some shelf blends and also whipping a blend up with what I have to work with please?

Off the shelf brands: Fox Farm (happy frog blend for seedlings and ocean forest for mature plants); Pro Mix; EB Stone Recipe 420; Coast of Maine are all shelf products that will work okay. You can really use most soils sold as potting but stay away from anything with time release/slow release nitrogen in it. Miracle Grow and a few others have it and the lingering nitrogen can become a problem later down the road. The shelf products usually just need a couple of thoughtful amendments for them work out.

If you want to put something together with what you've got, pick up some sphagnum peat moss or buffered coco coir and some perlite and put it together as a blend with 40% peat or coco, 30% perlite and 30% of your compost.

This is an extremely basic blend and there's some other things you might want to load in, like some light supportive nutrients in amounts that support a good cannabis ratio like 3-1-2 and some things that help the soil behave better but they aren't really essential... Dolomite lime if ph tends to drift down/elemental sulfer if it tends to drift up; Gypsum to provide calcium sulfate and prevent soil compaction (especially helpful with peat blends that can see their structure collapse and compact during drybacks), Biochar for nutrient storage and buffering, and humic/fulvic acid for better nutrient availability, and worm castings (moisture retention, microbe inoculation and gentle N).

So for that seedling you currently have in compost... If you throw some peat, perlite and your compost together and repot that little plant into it, you're going to at least give it a chance at surviving.
 
Thanks for the info!

I’m going to mix 70% coco, 20% worm castings, and 10% perlite.

Would this be a good mix?

Also, I’m going to be feeding my plants synthetically as they get older, so im wondering if PH will be issue?
 
40/30/30 is the basic ratio, is my understanding

I'm trying out the ProMix this year for my seedlings. (2nd Grow) I really like it so far.
Only thing I've done was add a light feeding of slow release organic fertilizer after the first week, Then a full dose the second week, and of course watering when needed.

Friday will make them 4wks old. These are photos that will be moved outdoors, next month. Well..some of them. I've got 9 regs to sex out, and 5 fems going.

IMG 20260404 173811

Chemdog X Hash plant
 
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