Guava is a very popular fruit. It is available throughout the year except during the summer season. Being very hardy, it gives an assured crop even with very little care. Its cost of production is also low because its requirements for fertilizer, irrigation and plant protection are not much. Further its nutritive value is very high. Therefore, it is and ideal fruit for the nutritional security. Guava is also grown as a backyard fruit to great extent. In India, the best quality guavas are produced in Uttar Pradesh, particularly in Allahabad region.
Climate and soil
Owing to its hardy nature, guava is grown successfully in tropical and subtropical regions up to 1, 500 m above mean sea-level. Best quality guavas are obtained where low night temperatures (10`C) prevail during winter season. It tolerates high temperatures and drought conditions in North India during summers but it is susceptible to severe frost as it can kill the young plants. An annual rainfall of about 100 cm is sufficient during the rainy season (July- September). The rains during harvesting period, however, deteriorate the quality of fruits.
Guava is cultivated on varied types of soils- heavy clay to very light sandy soils. Nevertheless, very good quality guavas are produced in river-basins. It tolerates a soil pH of 4.5- 8.2. Maximum concentration of its feeding roots is available up to 25 cm soil depth. Thus the top soil should be quite rich to provide enough nutrients for accelerating new growth which bears fruits.
The filed for planting is prepared during summer season by ploughing, leveling and removing weeds. The pits of 1m x1m x 1m size are dug and filled with a mixture of farmyard manure and soil. If soil is good and irrigation facilities are available, the preparation of land and digging of pits are not required. The planting is done during the rainy season by adopting square planting system.
Guava is commercially planted at a distance of 5-8 m. The exact planting distance is, however, decided according to variety, soil fertility and availability of irrigation facilities. Guava Lunknow 49 needs more spacing than apple guava and Allahabad Safeda. Under irrigation and high soil fertility, the plants become very vigorous requiring more spacing. In normal conditions, a planting distance of 7 m is optimum. High density planting reduces total soluble solids, sugars and ascorbic acid but increase irritable acidity. The lower plant population results in the spread of crown, while higher planting density causes erect growth of branches making the plant tall and compact. High density planting gives higher yield/ unit area in early years of fruiting.
Manuring and fertilization
Although guava is grown without the application of any manure and fertilizer, it responds very well to their application by giving higher yield and better quality fruits. For guava growing regions of the country, different fertilizer schedule- 600 g N, 400 g K in northern region; 260 g N, and 260 g K in eastern region; 900 g N, 600 g P and 600 g K in southern region and 600 g N, 300 g P and 300 g K/plant/year in western region, have been recommended. The fertilizer application should be based on leaf nutrient status of an orchard, wherever feasible.
Time of fertilizer application depends on the crop taken and the region. In north India, fertilizer is given in the first week of May for rainy season crop and in first week of July for winter season crop. In West Bengal, fertilizers are applied in 2 equal split doses, one in January and the other August. At Bangalore, full K and 70%N are applied in June and full P and 30% N in September. Since 48% of feeder roots of guava are found in the surface soil up to 25 cm depth, the fertilizer should be placed in 25 cm trenches 1 m away from the trunk for better uptake.
Sometimes guava suffers a deficiency which is characterized by reduction in leaf size, intervenal chlorosis, and suppression of growth and dieback of leaders. It can be corrected by spraying of ZnSO4 (0.45kg) and hydrated lime (0.32 kg) in water (33 liters). Bronzing is another common problem in guava. It is caused by the deficiency of B, Zn, N, P and K Due to low soil pH the soluble P level of leave is a better index for bronzing. Guava Lucknow 49 is more susceptible then Allahabad Safeda. It can be reduced by improving the soil pH and treating the soil with N, P, K and Zn at 200, 80, 150 and 80 g/ year respectively, or fortnightly foliar spraying of these nutrients each at 2% for 4 months.
Guava is mostly grown under rain fed condition and irrigation is rarely practiced wherever this facility is available. However, irrigation enhances the yield of guava by making the plant more vigorous and increasing the fruit set. Irrigation is especially desirable after planting for survival of the plants and thereafter for 2-3 year to obtain early good growth. Irrigation of fruiting plants depends upon the adoption of a particular cropping pattern. For the whole year, cropping pattern which is commercially adopted all over the country except the northern region, irrigation is essential during summer season. Normally, winter season cropping pattern is adopted in north India which requires fortnightly irrigation during October-November. Irrigation is given to make the soil of root zone moist; thus heavy irrigation is unnecessary. The fruit quality of guava is adversely affected by high soil moisture content during harvesting.
Guava plants are attacked by wilt, which alone causes heavy losses. It is very difficult to find out an orchard of guava more than 30 years in age because most of its plants die at about 20 years of age due to wilt. Various fungi causing wilt are Fusarium roseum oxysporum, F. psiddi, F, solani, Macrophomina phaseolina and Gliocladium roseum. Resistant rootstock is the only solution. The planting material should not be obtained from a wilt infected region.