Jump to content
The Corroboree
Sign in to follow this  
gtarman

Pure coir for raising seeds...thoughts?

Recommended Posts

So I've been trying out these Brunnings seed-raising coir blocks from bunnings seeing as they're much easier to lug around than a 25L bag of potting mix. But so far my results have been mixed.

I haven't had it for quite enough time to make a full judgement just yet, but it doesn't seem like an ideal medium. Some things have germinated but many have not., while other mixes have had much better success rates and times.

One thing is that it seems to me like the moist coir is too heavy/dense and probably not aerated or well-draining enough. I think some seeds will struggle to push their way up through it, even with only a light covering. They just don't seem to be germinating in it readily compared to other regular mixes I have on hand.

Has anyone else tried this before? Have any thoughts?

Share this post


Link to post
Share on other sites

One thing is that it seems to me like the moist coir is too heavy/dense and probably not aerated or well-draining enough.

thats it

  • Like 2

Share this post


Link to post
Share on other sites

Yeah too soggy - it's better mixed with vermiculite, but even then the mix will be pretty nutrient deficient, so if you want to raise the seedlings up a bit I find you need to either liquid feed them or put some fine organic matter (old manure or compost or something) into the mix... And then if you're going to go that far I figure you might as well just add some sand/gravel & make up a proper seed-raising mix.

I found coir (or coir-rich mixtures) to work better for cuttings than seeds - especially when you can humidity-dome them, as this keeps the medium moist enough without watering, which reduces the risk of waterlogging.

Share this post


Link to post
Share on other sites

Peat pellets and then amended potting mix I reckon. I've got one of those Brunnings coir bricks sitting there for seedling purposes, but I've decided to keep it for part of a bulk substrate when the time comes. Just felt a bit too restrictive to me :wink:

Share this post


Link to post
Share on other sites

in pure coir you control the nutrients no?

that way the gardner must shoulder all the blame if leaves go yellow etc. it's an unforgiving medium but i like it. green mouldy things don't appear as easy as say-in vermiculite- so i like it. Ph is the key in coir. sometimes all you need is h2o and the nutrient sustainability that comes from the kernal of each seed you plant. some kernals have heaps of nutrient and will happily live for 2 months before a feed. Others, well, they emerge yellow and need a oomf lifdt in npk for the thing to push on, either way. i like the coir. I acyually sprouted some of my own open ben seeds in some coir in a cup sitting on the window ledge over winter. they look happy. i'll show a pic later/tomo.

coir is a medium, it has no(or very little nutirents for the need of most plants anyway) but i like it. Makes good filler too in soils. endless really, maybe builds houses too, who knows.

Share this post


Link to post
Share on other sites

ben openeth seeds post-4664-0-53363400-1443261720_thumb.jp

post-4664-0-25935400-1443261759_thumb.jp

and the petal brought home a worker friend's of hers samosa pork handmade for dinner.

post-4664-0-46968100-1443261845_thumb.jp

samosa

l&l

  • Like 2

Share this post


Link to post
Share on other sites

I found that the coir is great for germinating seeds but then nothing much happens. The plants just sit there. I have used seed raising mix which seems to help the new seedlings grow better.

Although the coir says there is some fertilizer in the mix I find that this is not enough to encourage much growth. You need to feed the plants continuously which is a pain. I got better results sowing seeds directly in my garden beds.

The last lot I sowed into the coir I transplanted fairly quickly after germination because again there was limited progress.

  • Like 3

Share this post


Link to post
Share on other sites

I found that the coir is great for germinating seeds but then nothing much happens. The plants just sit there. I have used seed raising mix which seems to help the new seedlings grow better.

Although the coir says there is some fertilizer in the mix I find that this is not enough to encourage much growth. You need to feed the plants continuously which is a pain. I got better results sowing seeds directly in my garden beds.

The last lot I sowed into the coir I transplanted fairly quickly after germination because again there was limited progress.

zazactyly, sprout germination rates are high in coir but then-as you say again minga :wink: growth stalled. i like coir and minga everyday with a slight cuppa of cammo.

  • Like 1

Share this post


Link to post
Share on other sites

tomato freaks get grown in coir., heavy feeders love coir.

massive tomato's.....but alas nothing beats earth bound roots that get micro nutrients like like trace elements in rock and raimfall

  • Like 2

Share this post


Link to post
Share on other sites

I've had success with coir, squeeze it till only a few drops of water comes out, it should be moist but not wet.

I've also had bad luck with unclean seeds spreading mould before they germinate.

I think the benefits of coir are that root damage is minimalised when transplanting seedlings, however all this is unscientific observations :P

  • Like 2

Share this post


Link to post
Share on other sites

I mix mine with perlite and vermiculite and will only use Canna coir as the bunnings brand is not treated properly (PH can be a nightmare ) But that being said I use the bricks with my compost instead of potting mix and have no issues .Just when cloning and seed raising i preffer to use the Canna brand with a mild nutrient solution (very mild )

  • Like 2

Share this post


Link to post
Share on other sites

Coir works really well, especially for seedlings... but it's very necessary to add a little sharp sand to the mix... I also like to add some compost to richen it up a bit.

Coir needs consistent fertilizer i've found, as it contains none on its own... I like using time release fertilizer like osmocote to get the necessary n-p-k, and usually a bit of lime & gpysum for minerals. Coir will stall your plants if you don't stay on top of a fertilizer regimen, while other mediums cut you more slack.

I love how cheap coir is... where I live it's actually the same price as bulk peat if not cheaper. Easy to store, etc... really has a sponge effect on soils; it's very hydrophilic, and doesn't ever compact. Supposedly the lifespan is around 3 times longer than peat- it takes 3 years instead of one to start going sour.

Share this post


Link to post
Share on other sites

Hmm. So I ended up throwing out a lot of my coir seed experiments today, most hadn't germinated and of the few that had they seemed to be struggling. My closing thoughts is that coir is probably a very good ingredient in mixes, but makes a poor mix on its own.

I've been realizing lately as well that perlite can be a good ingredient in the right amount, like coir I guess. I used to hate perlite because it would blow around and float up in the mix disturbing the roots but I think that's only really a problem when you use too much of it. I've had a lot of success using it up to 10% or so of a mix, seems to help things along. Everything in the right amount is good I think.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×