How To Grow Litchis ?
Temperature and humidity
• The average maximum temperature in the litchi-producing areas of South Africa should be at least 23 °C during October and 24 °C during November, with a relative humidity of 50 % and higher.
• The average monthly minimum temperature in areas where litchis are produced should be above 6 °C. Areas where heavy frost occurs are not suitable for litchi production. It should, however, be cold and dry enough in winter to ensure good dormancy.
• The minimum temperature in some Lowveld areas (Malelane and Komatipoort) does not drop low enough in winter to give the trees the proper dormancy period. Trees can be forced into dormancy by withholding water/irrigation during the 3 coldest months of the year. Producers must, however, ensure that especially young trees do not dry out.
Soil
• Litchis grow very well, especially in sandy soil in the cooler subtropical areas.
• However, the trees also grow and produce well in clay soil in warmer areas.
• Litchis are well adapted to different soil types.
Cultivars
Litchis were originally imported from China, India, Taiwan and Florida, USA. Cultivars grown in South Africa are divided into the following groups:
Mauritius group
This group is usually planted locally as well as abroad and
produces satisfactory yields and fruit of good quality, e.g.
H.L.H. Mauritius, Muzaffarpur, Late Large Red, Hazipur,
Saharanpur and Rose-Scented.
Chinese group
These trees produce very poor yields, but the fruit is of excellent quality and has a high percentage of chicken-tongue seeds. Cultivars include Haak Yip, Shang Shou Huai, Kontand, Glutinous Rice and Three Months Red.
Madras group
These trees bear colourful red fruit, but fruit quality is poor. Cultivars include Kafri, Shorts Seedless, Johnstone’s Favourite, Emmerson, Durbhanga, Maries, Mooragusha, Madras 19, Hazipur/Saharanpur, Red McLean, Brewster and Bedana.
Planting distance
A 25-year-old tree can reach a crown diameter of 12 m. If trees are widely spaced and later become uncontrollably big an economic yield will not be possible. If the trees are to be spaced closely together, size must be controlled from the start by pruning. Try to plant as many controllable trees as possible per hectare. A planting distance of 9 x 6 m is recommended for semi-intensive plantings.
Leaf analysis
Leaf analysis is the only technique according to which sensible fertilisation can be applied to a specific planting. The following aspects are important:
• The correct time for sampling is from mid-September to mid-November.
• The correct leaf must be sampled (see figure).
• The first leaf sample of a specific planting must be accompanied
by a soil sample.
• A leaf and soil sample must represent a planting of not more than 3 ha.
• The sampling method is
important:
– Select about 20 healthy trees, well distributed throughout the planting.
– The trees must be of homogeneous appearance and representative of the average trees in the planting.
– Sample 4 leaves per tree.
– Do not take samples from obviously good or weak trees.
Fertilisation
Do not fertilise newly-transplanted trees too soon. Fertiliser should only be applied about 1 year after transplanting. The applications must be very light and broadcast evenly, but not against the stems of the trees. Irrigate after applying fertiliser.
Phosphate (P)
All the phosphate is applied immediately after harvesting.
Potassium (K)
Half of the potassium fertiliser is applied just before flowering and the remainder after harvesting.
Zinc (Zn) and boron (B)
Zinc must be applied at least 4 times a year. The following substances and concentrations are recommended per 100 l of water:
• Zinc oxide at 200 g or
• NZN at 150 ml or
• Agri-zinc at 50 ml.
Spray the trees from soon after planting with 100 g borax or 75 g Solubor/100 l water every 2 years.
Organic fertiliser
Kraal or chicken manure can be used as additional fertiliser at 2 or 1 kg respectively per mature (10 years) tree, spread evenly in the drip area. However, if no other fertiliser is available, kraal manure can be applied as follows:
Covering litchi fruit clusters
• Covering the fruit with paperbags prevents damage from fruitflies and litchi moths, as well as sunburn and cracking.
• The best time for covering the clusters will vary from one locality to the next.
• Paperbags are at present the most suitable and also the cheapest covering material.
• The fruit develops a very attractive red colour inside the paperbags.
• Covering the fruit also extends the harvest period because fruit can be left on the tree for a longer period.
• The paperbag at present used is open at both ends. It is made from reinforced brown paper that is very resistant to the elements.
Litchi moth
• The fruit must, however, be covered in the correct way and during the right time of the day (not early in the morning or immediately after rain), because of the risk of decay when covered while still wet. Spray against litchi moth and fruitflies just before covering.
• Remove all the leaves on the cluster stem before covering.
• Do not put more than 25 litchis in one bag.
• The bags must be fixed to hang to an angle to allow water to flow out.
• Both sides of the bag must be closed and, if necessary, a small opening must be left for rainwater to run out. The open ends can easily and quickly be stapled together.
• The paperbags will even keep fruit bats and birds away.
• Another advantage is that the fruit is handled less during harvesting and this limits damage caused by rough handling.
• When removed carefully, the bag can be used for another season.
Insect pests
Important pests include bark borers, litchi moth and fruitflies. Consult your nearest extension officer about ways to control these insects.
Harvesting
• The stage of maturity at which fruit is harvested is one of the most important factors that determine the ultimate quality at the point of sale.
• Litchis do not develop further after picking. The fruit must therefore remain on the tree until quite ripe.
• Litchis harvested too early have an unattractive colour and have a sour taste