Its a very good question . It is commonly seen a spurt of weed growth following the application of compost . I would go ahead with incorporation of compost before sowing of cover crops so that both cover crops and succeeding main crop , both  are mutually benefitted...

Thanks for your reply, How we can prepare growing bed for succeeding main crop after terminating cover crop?

Its a very good question

Its mix five species cover crop cocktail

An intelligent question. compost can be incorporated in soil, prior to sowing of any crop. may be cover or cereal crop. Compost is a slow release organic fertilizer that will provide macro and micro nutrients to the test crop. . 

Incorporating compost before planting cover crops will benefit the cover crops because the compost may provide necessary nutrients and microorganisms to the cover crops to grow vigorously fix nitrogen from the air.

An ideal soil does not need any application of inputs, because it would have all the physical, chemical and biological characteristics of the soil, necessary to achieve a good production. The need for application of certain materials depends on the level of degradation of the soil or the insufficiencies for production. If what is applied does not cover the deficiencies of the soil, there is not considerable utility. In many cases it is convenient to analyze the content of the materials to be applied to estimate the quality and quantity to be applied. Even cover crops are plant species that require acceptable soil conditions and nutrients, and that their function is to only have nutrients available in the following period after being incorporated into the soil, assuming that their goal is to improve soil nutrient levels . Therefore, incorporating compost will surely improve your performance. Consider that all organic material applied is not mineralized in the soil in the first year, so the application must be constant, taking into account that all nutrients must be found in the soil, according to the phenological stage of the species in cultivation, as well for the harvest of interest.

Nutrient release in compost is slow unlike mineral fertilizer. We may need to considered how long the cover crop will stay on the field and the interval between compost application and planting. Considering that in low fertility soil, most leguminous plants only require nutrient addition at the early stage and the adverse effect of alkanility (which could result from compost addition) on nodulation, the answer to this question is YES and NO. In summary, this depends on many other factors.

Hi Vahid,

This is an important question and a relevant conundrum in organic agriculture. First, the Compost /manure application in cover crop depends on how you want to plant your next cash crop (say corn). If your next corn is going to be no-till planted, you would want to apply compost prior to cover crop planting assuming that the cover crop will transfer that N to the cash crop next season. For example, you can apply compost and incorporate it and plant hairy vetch-triticale cover crop in the early fall. Around next June, you can roll the cover crop residue and no-till plant corn. On the other hand, there is no need to apply compost in the cover crop if your next cash crop would be tilled. Both legume (vetch) and non-legume (rye) can grow without application of compost.

Second, yes, you would always want to immediately incorporate manure/compost to reduce ammonia volatilization, which could be a substantial loss if you leave it on the surface. Also, depending on the time of application, incorporation might increase nitrous oxide emissions. The nitrous oxide emissions will behave differently in the two scenarios that I have explained earlier.

I hope this answers your question.

Hi Vahid,

I am of the view that, before one applies manure/compost, there's the need to know the nutrient requirement of the crop to be planted. The quantity of manure/compost that can provide the needed nutrients. You can then go ahead and incorporate compost to supply a higher quantity of the required nutrients and supplement the rest with the cover crops knowing exactly the quantity of nutrients the cover crops will provide. Meeting the crops nutrient requirement is very important and the way you go about it organically is not that important.

Applying compost with perfect c:N ratio equals to 24 can feed the microorganism in suitable amount, as a matter of fact , is not important to know plant nutrients  requirements, when we applying compost is not directly consumed by plant, the microorganisms uptake the compost first and make it the nutrients available for crops, so its very important keep C: N ratio of the soil for bacteria in optimal range by cover crop diversity and rotation

I agree with you Vahid, but what will be the final output of the microbes, Is your interest in the additions that they make or what to feed them. At the end you will have to meet the nutrient requirements of the crops.

Now here is the question, how we can measure the final output of bacteria meaning that the amount of available nutrients macro and micro nutrients for crops?

It's only possible when two sites , one practising cover crops and another site without cover crops are compared with regard to difference in available supply of  different nutrients..