Dr.Kalaivanan, I am not a horticulture specialist but as an agricultural student and scientist I have come across more literature supporting better use of foliar feeding  in orchard crops like citrus ,apple, grapes etc.,As I understand foliar  analysis and foliar feeding are common in horticulture .Your IIHR,Bangalore has developed micronutrient mixtures for  important fruit crops and they are very popular with farmers.It is an age old practice in citrus crop and we may come across lot of references  from California and Florida states in USA.However my literature review is not so recent.Soil testing and application of nutrients especially micronutrients  is not easy in tree crops but continuous application  of manures and recommended rates of fertilizers may benefit the tree crops also.However you may have to clarify me that how long  it takes soil applied nutrients to reach active roots in soil in orchard or tree crops.

The basic difference is very well developed rooting deep system of perennials. The uptake nutrient from a vast volume of soil (laterally and in depth) and are relatively lesser deficient in certain nutrients, especially micro nutrients. Therefore, aerial sprays reveal poor results as compared with annual or seasonal plants. 

Part of the observed difference has to do with the accelerated metabolism of the annuals and the different structures they build during their growth, and another crucial aspect is the leaf surface, which is often tougher and more waxy on plants that intend to keep their leaves for longer. Therefore, foliar uptake is relatively hindered in perennials while it is accelerated in many annuals.

The fact Joseph pointed out may also be on of the reasons for less response.  

There are basic differences between annual and perennial plants in  their architecture ,duration, total nutrient requirement , uptake from soil, fertilizer,manure and other sources. In case of perennials-the season, fresh growth in terms of fresh foliage put up in the season which is active in uptake,the synchronization between the active period of uptake and actual spray application,the concentration of nutrient/ nutrients applied,the coverage of whole foliage through spraying and number of sprays made will decide  ultimately  whether the requirement of plant are met or not.Meeting the requirement of annual plant is easy with 2-3 sprays at active growth stages and the  rest from soil.Conventionally soil  profile is examined and soil related constraints are removed before plant of saplings in orchards through amendments application including manure.As per the growth requirement of the crop, manure and fertilizers are applied in one or two seasons every year.Mainly micronutrients and some times Ca andMg are applied through foliage.Also meeting the full  requirement of micro nutrients is difficult because of low nutrient concentrations in the mixtures and limited number of sprays  made and improper coverage of whole plant/ tree.So the basic question remains that how far we can meet the nutrient requirement of perennial crops with the limitations we have as explained.

The annual crops to need fast response. The perennials trees normally have a good system of roots and are not defficient in micronutriets.

Jose supported my view point.

Dr.Hussain, lot of micronutriet mixtures are being used as foliar spray in horticulture in India. Also ,as roots will be in subsoil or lower horizons amount of nutrient present in available form is limited. So one has to go for foliar nutrition in perennial crops also ,with limitations we have as mentioned by me earlier.

Dr.Hussain, lot of micronutriet mixtures are being used as foliar spray in horticulture in India. Also ,as roots will be in subsoil or lower horizons amount of nutrient present in available form is limited. So one has to go for foliar nutrition in perennial crops also ,with limitations we have as mentioned by me earlier.

The question under discussion is not whether to use micronutrients' spray for perennials or not but why response of such plants is low. So we have to llok causes and factors. 

I do not believe that foliar fertilization is generally better in annuals than in perennial crops.Annual crops have a short growth cycle, more rapid growth and therefore seem to react better. Perennial crops like fruit trees have  different nutrient dynamics as they also feed on their nutrient reserves. Fruit trees like apples or grapevines  react very successfully to many types of foliar nutrient sprays (calcium or micronutrient sprays)

Mr.Alexander reply appears to be reasonable and  convincing. I  agree with him.

Mr.Alexander reply appears to be reasonable and  convincing. I  agree with him.

Though response to foliar application depends upon many factors; need by plant for the nutrient being sprayed is the deciding factor. If it is not deficient, slow or no response is expected.

The following paper provides good information on foliar nutrition of orchard crops.Uptake of mineral nutrients from foliar fertilization(review)Pawel Wojcik

Journal of fruit and ornamental plant research:12,2004 special ed.

Foliar applications, Foliar sprays are important aspects for yield enhancement. I think by using this Foliar spray technology, one could provide maximum efficiency of nutrients required by Plants.

If we could mix a small amount of 0.03-0.05 % of silicone based adjuvant with micronutrients and liquid fertilizers, it will act as performance maximizer, a kind of booster and plant could get best results and finally best YIELD. 

Thank you, 

Dr. Bilson Shukla ([email protected])

Mr.Imran,Good comprehension and good summation.But your first sentence needs some correction. Foliar application of nutrients can not provide large amounts of nutrients and meet bulk  nutrient requirement especially in case of major nutrients as they are required in large amounts and it is difficult to supply large amount through foliar application .Foliar application is to supplement the soil  and manure/fertilizer supply.But for some micronutrients like Zn and B, foliar application can meet the requirement to a  large extent especially in annual crops.

Well pointed out by Dr. Rao that major amounts cannot be applied through foliar sprays. This practice is just a supplemental farm activity when immediate uptake of a certain nutrient during peak growth stage is required.