In Cairns, the earliest varieties begin flowering in late August and early September and nut drop begins in mid-October. The nut develops first and the apple fills out during the last fortnight before nut drop occurs. The flowering season varies in response to the weather and the variety, but it usually extends over 3 to 4 months.Īfter pollination, the fruit takes 6 to 8 weeks to develop. Thus flowers and fruit are borne on the outer extremity of the canopy.īoth male and bisexual flowers are produced, with male flowers predominating for the first month. Flowers are produced at the end of the new shoots. Selections from the yellow to fawn range have been found to have the best resistance to anthracnose and to be associated with the best yield performance.įlowering normally occurs following the growth flush at the end of the wet season, but its timing and duration are strongly influenced by temperature. Apple colour ranges from bright red to bright yellow. The nuts (kernel and shell) should weigh 8 to 9 g, with a minimum of 6 g, and have a specific gravity of at least 1.0. Selected trees may be reproduced by vegetative propagation methods such as budding or grafting onto seedlings, layering or cuttings.Ĭharacteristics to select for include vigorous growth and good, early fruit set. Many of these lines have been given varietal names.
However, in some overseas producing districts, generations of growers have selected seed lines that reproduce some characteristics reliably. Such trees are easily blown over during the wet season.Īs self-pollination and open pollination both play a part in cashew seed production, seedlings tend to be highly variable, and no true-to-type varieties are reproduced from seed. Shallow soils give rise to a poorly-developed root system with consequent low drought tolerance and unthrifty top growth. Deep sands, sandy loams, gravelly soils and red latosols have been found to be physically ideal, although the lighter soils require special care with nutrition.
#Cashew growing on a tree full#
In deep friable soils, full development of the extensive lateral root system occurs, and the deep taproot system reaches several metres in length and can sustain the tree through long dry seasons. Sprouting occurs after about 4 days of damp conditions.Ĭashews tolerate a wide range of soil types, but the best growth and production occur in deep, well-drained sands or loams. Rain during the harvesting period when the nuts are on the ground causes them to deteriorate rapidly. As the nut and apple are developing, rain causes rots and severe crop losses. Rain during flowering results in the development of the fungus disease anthracnose, which causes flower drop. Ideally, there should be no rain from the onset of flowering until after harvesting is completed. Similarly, two dry seasons induce two flowering flushes. Well-distributed rainfall tends to produce constant flowering, but a well-defined dry season induces a single flush of flowering, early in the dry season. Established cashew trees in deep soil have a well-developed, deep root system, allowing trees to adapt to long dry seasons. Young trees in particular are very susceptible to frost, and cool spring conditions tend to delay flowering.Īnnual precipitation may be as low as 1000 mm, provided by rain or irrigation, but 1500 to 2000 mm is considered optimum. Although cashews can withstand high temperatures, a monthly average of 27☌ is considered optimum. Close to the equator, the trees grow at altitudes up to about 1500 m, but the maximum elevation decreases to sea level at higher latitudes. Cashew trees grow in a wide range of climates between the latitudes of around 25 ° north or south of the equator.
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