Dear Mohammed Abdalla Elsheikh,

Please check the following ResearchGate links.

Article INFLUENCE OF SOIL AND FOLIAR APPLIED FERTILIZERS ON SUGARCAN...

Article EFFECT OF SOME NEWLY INTRODUCED FERTILIZERS IN SUGARCANE

Article Iron, Manganese and Sulphur Uptake and Nutrients Availabilit...

Article Evaluation of different foliar fertilizers on the crop produ...

Article Timing potassium fertilizer applications to sugarcane in Mauritius

Good luck!

As concerns your sugarcane question; am not a crop scientist, soil scientist nor agronomist however I am practitioner and grow sugarcane. The best time to apply foliar fertilizer is often after weeding. This results in robust growth and higher yields.

Try to imagine matching application rates with growth. However, there are cost implications .

Practically for the grower of the sugarcane Nutrients foliar application is best at the stage of tillering and after the earthing up. Tillering starts from around 40 days after planting and may last up to 120 days. Early formed tillers give rise to thicker and heavier stalks. Late formed tillers either die or remain short or immature. Tillering provides the crop with appropriate number of stalks required for a good yield. Maximum tiller population reaches around 90-120 days after planting. By about 150-180 days, atleast 50 per cent of the shoots die and a stable population is established. Encouraging good tillering is important to build adequate population. So these stages are very important to get the maximum yield and so you can use foliar application of nutrients during this stage. Moreover, you can also apply at any stage when the plant shows the symptoms of deficiency at any stage.

well peak vegetative stage is the best.However this varies with weather,climate and zones.In North India ,this stage comes from June-August.

I agree with Muhanmmad Shoaib Rana,

Tillering stage is a good stage to apply micronutrients using foliar application.

It is early enough to have enough foliage of effective absorption nutrients such as zinc which is often limiting and there is sufficient time for action to manifest. Ideally the foliar nutrient analysis would be employed and then the foliar application can be tailored to gaps in the nutrition. Zinc will be potentially problematic in alkaline and in too acid soils with low soil zinc.

Teaming leaf analysis with the application of appropriate foliar application could be followed with a subsequent analysis to confirm the nutritional requirements have been satisfied.

After having a experience with the site and reaction the application might be able to applied according to visual clues such as plant color and vigor. By combining analysis with observation analysis will become less critical for the practical application.

A best case scenario is to have a soil analysis and use soil balancing so foliar applications may be necessary and avoided.

Major nutrient for sugarcane would show a change according to plant stage of phenology. For the rooting and sprouting the application P is of primary importance. From the tillering stage N is of most responsiveness. For the preparing for the harvest potassium becomes the primary agent of sugar translocation and late season disease tolerance.

Tillering period is best for foliar application of the nutrients in sugarcane crop. N, K, Zn and Fe are being applied on a large scale in sugarcane growing areas of India. Tillering period is between 35 to 120 days after planting or April to June. Tillers are converted into millable canes so it is must to have maximum survival of tillers. So if there is water stress during this period, foliar spray can be more useful to overcome the adverse effect of water stress. There should be optimum moisture in the soil, field should be weed free and sufficient foliage at the time of foliar application of nutrients. Generally 2.5 % of N and K2O are applied through foliar through Urea and Murate of potash.

foliar spray efficiency in any crop depends (among other factors) on the sprayed surface and that means you should chose the time of maximum surface area of the crop.

The best timing is when the plant has the biggest foliage unless there is a need to spray earlier than that (i.e. to cure nutrient deficiency)