Custard Apple Water and Nutrient Requirements: A Season-Wise Management Guide

Research published by the Central Research Institute for Dryland Agriculture Hyderabad and ICAR-NRC for Arid Horticulture establishes precise water and nutrient requirement data for custard apple across each distinct phenological growth stage from dormancy through harvest. CRIDA field trials conducted across dryland custard apple orchards in Maharashtra, Andhra Pradesh, and Telangana demonstrate that targeted supplemental irrigation at three critical growth stages combined with split fertiliser application timed to match crop demand periods increases total marketable yield by 30 to 40 percent while simultaneously reducing total water use by 25 percent and fertiliser input cost by 20 percent compared to conventional uniform irrigation and blanket fertiliser application schedules used by most farmers. Understanding the seasonal growth cycle of custard apple and matching inputs precisely to crop demand at each stage is the foundation of profitable and resource-efficient orchard management.

Understanding the Custard Apple Annual Growth Cycle

ICAR phenology research documents that custard apple in the Deccan Plateau and dryland Maharashtra follows a predictable annual growth cycle with four distinct phases that determine irrigation and fertiliser management decisions. The dormancy phase from January to March follows harvest completion, during which trees shed most leaves and enter a rest period with minimal water and nutrient demand. The new flush and flowering phase from April to July triggered by pre-monsoon showers and rising temperatures is when new leaf growth and flower bud initiation occur simultaneously, representing the most critical period for nutrition management. The fruit set and development phase from July to October during the active monsoon period is when pollinated flowers develop into growing fruits requiring adequate but not excessive soil moisture. The ripening and harvest phase from October to December is when fruits reach maturity and are sequentially harvested over a 6 to 8 week period. Each phase has specific water and nutrient requirements documented in CRIDA and ICAR research that differ significantly from each other.

Critical Irrigation Periods and Water Requirements

CRIDA Hyderabad irrigation scheduling research for custard apple identifies three critical irrigation windows where water stress causes disproportionately large yield reductions compared to water stress at other times. The first critical period is March to May before monsoon onset when providing 3 to 4 irrigations of 30 to 40 litres per tree at 15 day intervals breaks dormancy uniformly across all trees in the orchard, promotes synchronised new flush emergence, and advances flowering by 15 to 20 days allowing early season fruit to capture premium August market prices. The second critical period is September to October during late fruit development when supplemental irrigation of 25 to 30 litres per tree at 10 day intervals during any extended dry spell within the monsoon prevents fruit shrinkage and premature drop that CRIDA research documents causes 15 to 20 percent marketable yield loss in drought years. The third critical period is November to December during harvest when light irrigation every 15 days maintains fruit quality and extends the harvest window by 7 to 10 days. Total seasonal water requirement for custard apple under supplemental irrigation is documented by CRIDA at 400 to 600 litres per tree per year, significantly lower than mango at 800 to 1,200 litres and citrus at 1,000 to 1,500 litres.

Drip Irrigation Scheduling for Custard Apple

Research from ICAR-NRCAH Bikaner on drip irrigation scheduling for custard apple recommends a daily drip application of 4 to 6 litres per tree during the March to May pre-monsoon critical irrigation period using two drippers of 2 litre per hour capacity placed 60 cm from the trunk on opposite sides. During the active monsoon from June to September, drip irrigation is completely suspended unless there is a dry spell exceeding 21 days without rainfall. In October and November during late ripening and harvest, drip application of 3 to 4 litres per tree on alternate days maintains fruit turgor and skin quality. Tensiometer-based irrigation scheduling trials at ICAR-NRCAH showed that maintaining soil moisture tension between 40 and 60 centibars at 30 cm depth in the active root zone throughout the growing season gave the highest yield and fruit quality outcomes while using 35 to 40 percent less water than fixed schedule drip irrigation, making tensiometer-guided irrigation the most efficient management system for commercial custard apple orchards with drip infrastructure.

Macronutrient Requirements and Split Application Schedule

Fertiliser dose and timing research from Mahatma Phule Krishi Vidyapeeth Rahuri establishes the recommended annual nutrient schedule for a mature custard apple tree from the fifth year onward. Total annual nitrogen requirement is 500 grams per tree, split into three equal doses applied in May before monsoon, in August during active fruit development, and in October at fruit maturity stage. Phosphorus at 250 grams per tree is applied as a single dose in May mixed into the root zone soil as it is relatively immobile and does not require split application. Potassium at 500 grams per tree is split equally between May and September applications, as potassium plays a critical role in fruit sugar accumulation and skin colour development during the ripening phase. MPKV trial data shows that applying the full nitrogen dose in a single application as practised by many farmers results in 25 to 30 percent nitrogen loss through leaching and volatilisation compared to split application, meaning single-dose farmers are both wasting fertiliser cost and achieving lower yield responses from the same total input quantity.

Micronutrient Management for Fruit Quality

Research from Anand Agricultural University and IIHR Bangalore identifies zinc, boron, and iron deficiency as the three most commonly occurring micronutrient disorders in Indian custard apple orchards, with each deficiency causing specific yield and quality losses that are often misdiagnosed as disease or water stress symptoms. Zinc deficiency, characterised by small crinkled new leaves with yellowing between veins, reduces fruit set and causes small misshapen fruits. Soil application of 25 grams zinc sulphate per tree in June or foliar spray of 0.5 percent zinc sulphate solution at new flush stage corrects deficiency within one season. Boron deficiency causes flower and young fruit drop and is corrected by foliar spray of 0.3 percent borax solution at early flowering stage in July, which IIHR research shows reduces flower drop by 20 to 25 percent in deficient orchards. Iron deficiency causing interveinal yellowing of young leaves on alkaline soils is treated by soil acidification using sulphur at 500 grams per tree or chelated iron foliar spray at 0.5 percent concentration. Soil and leaf tissue testing conducted through the nearest Krishi Vigyan Kendra laboratory every two years is the most cost-effective way to identify which micronutrients are deficient in a specific orchard before applying corrective treatments.