Agriculture Reference
In-Depth Information
system is practised in Taiwan to maintain small tree size (<2 m), to obtain a
wine-glass shape, to encourage regular fl owering and for ease of management
and harvesting (Yen, 1995). An inverted cone approach is also used: wide at
the bottom and narrow at the top (3-4 m high), with mechanical trimming
to maintain shape. Tree thinning is also practised after harvest, to open the
canopy for light penetration, which is benefi cial for infl orescence formation
(Lin
et al.
, 1991). Light pruning sometimes encourages several weak fl ushes
and results in poor fl owering. Severe heading-back of a tree is harmful to
future infl orescence formation. Little or no pruning is done in India and
yields are said to be heavier than with the pruning practised in Taiwan.
Canopy thinning after harvest is done in India. Panicle thinning or pruning is
sometimes practised. Girdling is practised in October to inhibit new fl ushes; if
too severe the next year's growth will be reduced (Yen, 1995).
Fertilization
Fertilization practices of commercial litchi (Table 9.5) and longan orchards
dif er due to dif erences in climate, soil, availability of dif erent kinds of
organic and inorganic fertilizers and other factors. The Chinese practice
for litchi on alluvial or red basaltic soils provides 300-400 g of urea, 100 g
superphosphate and 25-50 kg animal manure to large trees just after
harvest, but not later than July. At blossoming, 100 g urea/tree or mixed
NPK is applied. To prevent fruit drop, trees are sprayed with 0.1-0.2% urea;
sometimes 0.2% magnesium sulfate is added.
A light fertilization application should be given with care immediately
after fi eld transplanting, due to the sensitivity of litchi roots to fertilizer burns.
Heavy applications should be delayed a year or after one or two growth
fl ushes. One-year-old trees are given ~30 g urea/plant/month. Also, 30 g of
a high-analysis mixed fertilizer such as 15-4-11 is given every 3 months with
Table 9.5.
General guide for litchi fertilization.
Year
Fertilizer formation
Time of application
Amount (g/tree)
First year
14-14-14
At planting time
125
14-14-14
At 4 months
125
14-14-14
At 8 months
125
14-14-14
At 12 months
125
Second year
14-14-14
Once/4 months
250
Third year
14-14-14
Once/3 months
455
Fourth year
14-14-14
Once/3 months
455
Fifth year
10-20-20
Appearance of
fl
owers
(Feb, Mar)
1000-1500
14-14-14
After harvest (May-June)
1000-1500
