I posted this elsewhere, but its highly relevant here in light of organic amendments etc and time to grow being the key with MJ..
Ok, so Alan and I have been discussing various soil amendments and relationships between microbes, available Nitrogen and the time to decay being of primary importance. To make a point here, I have chosen Seaweed, Kelp or Brown Seaweed, no matter. Lets consider its addition and what this means in real terms to a grower expecting some result near instantly.
When seaweed, or indeed any under-composted organic matter, is put into the soil, it is attacked by bacteria which break the material down into simpler units -- in a word, decompose it. To do this effectively the bacteria need nitrogen, and this they take from the first available source, this usually being the soil. This means that after seaweed has been added to the soil, there is a period during which the amount of soil nitrogen available to plants is reduced. During this period seed germination, and the feeding and growth of plants, can be inhibited to greater or lesser degree. This temporary nitrogen deficiency is brought about when any under composted vegetable matter is added to the soil. In the case of straw, for example, which is ploughed in after harvest, bacteria use up soil nitrogen in breaking down its cellulose, so that a 'latent' period follows.
Farmers in the past, and even today to a lesser extent, burn stubble after harvest to avoid this latent period, and the short-term loss of available nitrogen which causes it. But such stubble-burning is done at the cost of soil structure, soil fertility, and long-term supplies of nitrogen which ultimately would have been released from the decomposed straw. Today we have a product that can activate decomposition at a far higher rate than if we left the matter and or hoped to till it in after harvest and hope its gone come time to plant again.
It has been said by one authority that the latent period following the application of seaweed to the soil is one of fifteen weeks. But during this period, while there is a temporary shortage of available nitrogen, total nitrogen in the soil is being increased. This increase makes itself felt after the seaweed is completely broken down. Total nitrogen then becomes available to the plant, and there is a corresponding upsurge in plant growth. This knowledge of relevant decay rates for organic inputs, will help growers better understand the limitations of fixed organic inputs such as Kelp Meal, Guano, Manure, Wood Chip and so on, but more, will help you guys understand the critical nature of ensuring a flow of readily available plant N to pick up the BioN shortfall during conversion. It it also worth noting, Applications of Nitrogen should be tapered towards the decay rate marker. In the case of Seaweed Meal this would be week 15 plus or minus 1 week depending on relative humidity, and temperature rates.
It is therefore clear that while seaweed, in common with all organic matter, is beneficial to soil and plant, it has to be broken down, or decomposed, before its benefits are available. (I have already pointed out, but repeat it here, that liquid seaweed extract is not subject to this latent period. The nutrients and other substances it contains are available to the plant at once, however, in processing to liquid states kind of changes the use case as its more of an instant fix, with nothing latent where meal is a slower release and more cost effective, less prone to mold, unlike liquid kelp which if not kept cool and dark will spoil really fast.
This period of decomposition -- or composting, as gardeners know it -- usually extends over months rather than the time it might take to grow a short day crop. It can, however, be reduced by the use of dried blood and loam according to the technique invented by Mr. L. C. Chilcott. Only fourteen days of heating up are required before the mixture is used, and no latent period follows. I can provide details for those of you interested.
Hope this helps you guys when you are out and about talking to folks about Organix and dont forget, it is the inherent need for microbes to convert organic matter that means they often rob Nitrogen from our growing plants until a balance of decay is met. This is what is meant when people say "I cook my soil". It is the time taken to decay all or most or some of the organic inputs before planting. To know if you need Nitrogen, a simple calculation will help BioN = BioC/8
Happy growing with Organix :)
Eco