Simon Cole
Member
Hello my friends,
I have been working with organic composts this year, and I have diagnosed a immobile micro-nutrient deficiency across a polytunnel.
The problem is due to an incredibly high phosphorous load recorded in the compost and plant tissue. This has bound up one of the immobile nutrients in the soil but we are not sure which one. The head gardener used bat poo. I have leached most of the phosphate out now, and I dosed with calcium and magnesium (also as foliar application): It made no difference. I am therefore confident through the power of deduction that it will be something like Zn or S. The mix also contained a lot of peat so we don't have an ideal buffering capacity.
I cannot find a decent trace mix locally and Royal Mail are consistently taking up to two weeks to deliver 1st class post where we are working, never less than 7 days. The only thing we could get hold of was Tropica premium, which looked ideal to make into a foliar spray.
I have read in places that foliar sprays need to be several times the concentration of root feeds. I know that aquatic fertilisers like Tropica can be a little bit light.
Any recommendations for the dilution factor?
Also, how long does that stuff last on a shop shelf?
- It is a clear bottle and must have been exposed to UV - which I know is bad for iron stability - what about Zn, Mg and S?
Glad that this post is a little bit off piste for once
I have been working with organic composts this year, and I have diagnosed a immobile micro-nutrient deficiency across a polytunnel.
The problem is due to an incredibly high phosphorous load recorded in the compost and plant tissue. This has bound up one of the immobile nutrients in the soil but we are not sure which one. The head gardener used bat poo. I have leached most of the phosphate out now, and I dosed with calcium and magnesium (also as foliar application): It made no difference. I am therefore confident through the power of deduction that it will be something like Zn or S. The mix also contained a lot of peat so we don't have an ideal buffering capacity.
I cannot find a decent trace mix locally and Royal Mail are consistently taking up to two weeks to deliver 1st class post where we are working, never less than 7 days. The only thing we could get hold of was Tropica premium, which looked ideal to make into a foliar spray.
I have read in places that foliar sprays need to be several times the concentration of root feeds. I know that aquatic fertilisers like Tropica can be a little bit light.
Any recommendations for the dilution factor?
Also, how long does that stuff last on a shop shelf?
- It is a clear bottle and must have been exposed to UV - which I know is bad for iron stability - what about Zn, Mg and S?
Glad that this post is a little bit off piste for once
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