They are basically calcium which is a growth regulator and essential for plant growth. It is required for development of cell walls and there are huge volumes of studies each of which shows more reasons for it being necessary.

Jon

Crab, Clam, Oyster and Egg shells all contain Calcium so should be available for any place that sells animal feed supplies, I would think.( Crushed or ground)
Faye

you sea coast folks.. ought to visit the mainland some time...

when you suggest.. that the shells of anything.. are commonly available ....

in 55 years.. i have NEVER seen them in a MI nursery.. and i have visited a few ...

i am not aware of plants needing Ca ... in any significant amounts...

but it wouldnt surprise.. me if they dont do the same thing chunks of bark do.. and that is make a media more porous ... for better water flo management ...

maybe coastline soils are Ca deficient.. so it used as a SOIL amendment...

but that doesnt answer why you would need such in a potting media ...

i hope calcium is Ca... lol ...

ken

ps: in other words.. it might be a regional thing... i dont know if i would pay a premium.. to have it shipped hundreds of miles inland ...

I can't remember what Mocc said, but it has another purpose. It's not calcium. She'll answer soon.

bk

what's in the crab shells feed good bacteria that eat nematodes, more or less.

edited for typo

This post was edited by funnthsun on Tue, Jun 3, 14 at 19:11

The shells also contain chitin which helps trigger plants' defense mechanisms.

tj

Wait a minute here, I get them not for the calcium. Sure, it has some. But mainly it is chitin. Check that one out.

It is not a nematicide or anything, but it feeds the good nematodes which eat the bad nematodes, and I'm all for that. I don't know if that is true or not, but I'm waiting waiting for FedEx to deliver another 50 lb bag of it from Amazon. You can also order various other sizes of it direct from the manufacturer, Neptune's Harvest. I understand they are in Glouster MA (Perfect Storm). I noted though that the crabs and lobsters so crushed were CANADIAN.

Wouldn't it be interesting if Canada does not allow the sale of said product? But, I hope anyone who wants some can find them.

I cannot say they are effective or not for the purpose I assign them. I can SAY that my nematode problem is reduced, there are fewer signs of them that I've noticed. I can also say that the crab shells keep away elephants too, because I sure have yet to see one here.

The bag has a distinct odor, so outdoor storage is best. Like I keep mine in a galvanized garbage can. Things like raccoons and squirrels can gnaw through plastic containers.

I add a link below to the page on the mfgr website for the 4 lb bag. It has info about using it.

Here is a link that might be useful: Neptune's Harvest crab shell

What do bad nematodes do?

Well, PaulaB, I thought someone would never ask.

This is the story I tell my baby hosta to put them to sleep. It's a scary fairy tale about the bad nematodes and the good nematodes and the brave hostas.

This picture shows there are bad nematodes lurking, preying on unsuspecting young hosta.

And then the good crabs shells, crushed as they were, brought the good nematodes in to save the world of hosta from the evil nematodes. However, I don't have a picture of them living happily ever after.

As a side note....

I discovered something when I googled for Neptune Harvests crab shells. It is of course organic....or anyway, about as organic as anything can which lives in our polluted seas....and I noted that it is the hot fertilizer used by medical marijuana growers. Probably the NON medicinal growers too, but they ain't talking about it.

So if it's good enough for the pot growers, who give the very best care to producing big fine plants, it sure is testimonial enough to convince me. I'm a pot grower too.

Everybody say "Amen!"
:)

AAAAAAAAAAAAA

men!

'INTRODUCTION

Calcium is an essential plant nutrient. As the divalent cation (Ca2+), it is required for structural roles in the cell wall and membranes, as a counterâÂÂcation for inorganic and organic anions in the vacuole, and as an intracellular messenger in the cytosol (Marschner, 1995). Calcium deficiency is rare in nature, but excessive Ca restricts plant communities on calcareous soils. Calcium is taken up by roots from the soil solution and delivered to the shoot via the xylem. It may traverse the root either through the cytoplasm of cells linked by plasmodesmata (the symplast) or through the spaces between cells (the apoplast). The relative contributions of the apoplastic and symplastic pathways to the delivery of Ca to the xylem are unknown (White, 2001). However, the movement of Ca through these pathways must be finely balanced to allow root cells to signal using cytosolic Ca2+ concentration ([Ca2+]cyt), control the rate of Ca delivery to the xylem, and prevent the accumulation of toxic cations in the shoot.

Calcium enters plant cells through Ca2+âÂÂpermeable ion channels in their plasma membranes (White, 2000). Since a high [Ca2+]cyt is cytotoxic, a submicromolar [Ca2+]cyt is maintained in unstimulated cells by Ca2+âÂÂATPases and H+/Ca2+âÂÂantiporters (Sze et al., 2000; Hirschi, 2001). These enzymes remove cytosolic Ca2+ to either the apoplast or the lumen of intracellular organelles, such as the vacuole or endoplasmic reticulum (ER). The rapid influx of Ca2+ through cation channels in the plasma membrane, tonoplast and/or ER generates [Ca2+]cyt perturbations that initiate cellular responses to a diverse range of developmental cues and environmental challenges (White, 2000; Sanders et al., 2002). Proteins that change conformation or catalytic activity upon binding Ca2+, such as calmodulin (CaM), calcineurin BâÂÂlike proteins (CBLs) and Ca2+âÂÂdependent protein kinases (CDPKs), allow the cellular perception and transduction of the [Ca2+]cyt signal. These proteins are termed âÂÂ[Ca2+]cyt sensorsâÂÂ. It is speculated that cellular responses to specific biotic and abiotic stimuli are encoded by distinct [Ca2+]cyt perturbations and are transduced by particular [Ca2+]cyt sensors. Much current work on Ca in plants is dedicated to understanding the nature and specificity of [Ca2+]cyt signalling and response networks. '

As stated calcium is very much necessary, is rarely needed as a supplement and can be a problem in large amounts in a garden and might help if you have a rare calcium deficiency. I guess prolonged use (many years) might cause a problem....or not.

Jon; Who has learned something new again today.

Here is a link that might be useful: Let's see what the botanists say

This post was edited by jonnyb023 on Wed, Jun 4, 14 at 8:50

Jonny, I'll get my DH to interpret that for me so I can understand it. I'm sticking with the good nematode story for now. More my speed. :)

That is a very esoteric article, you know.

Quite. I suppose I am one of the few because I find this fascinatingâ¦perhaps that doesn't mean that I understand if fully, though - lol

Crab shells are very difficult to come by around here. What about gypsum considering my soil is alkaline?

This post was edited by paula_b_gardener on Wed, Jun 4, 14 at 11:34

Here you go!

Here is a link that might be useful: oyster shells

btw - I bought oyster shells on the way home from work today :) Then when I arrived home, I read your post, funny.

How much do I put in one pot? Obviously it depends upon the size of the pot, but a rough idea would be most helpful.