RAMBUTAN - HAIRY THING FROM THE FOREST
(One of a series of articles about growing fruit trees
in Samoa, written by Digby Gotts and published in the 'Samoa Observer'
between December 2000 and April 2001)
Any day in February in the Fugalei Market, you should start to see some
golf ball size and bright red fruit covered in hairy threads. These are
rambutan (lamutana in Samoan), a fruit native to Indonesia that have proven
to grow very well here, preferring the hot and wet climate of the coast
to the cooler climate of the hills. Rambutan translates from Indonesian
as “hairy thing from the forest” and is a word I have often
heard said about me as I push my way through Indonesian markets.
These fruits may look a little unusual, but once you break open the hairy
shell the sweet melting flesh has few equals. It is much sweeter and a
little larger than the lychee, a similar but non-hairy fruit from China
unlikely to grow well in Samoa. Rambutan is best eaten fresh, but is so
delicious that it is very difficult to simply eat one or two.
The trees can produce fruit in 4 years and by the time they are ten years
old, can produce 400 kilograms of fruit every year. Seeds grow well, but
unfortunately about half of these grow up to be male, and will never produce
fruit. The female trees can produce fruit but the flesh is often strongly
attached to the seed, a bit like mango, making it difficult to eat. Rambutan
trees are normally grafted, producing a more compact tree with easy eating
and well-flavoured fruit. The adult tree should be fed with one kilo of
NPK at flowering and another at harvest, along with a monthly micronutrient
spray. It will also help a second crop if the tree is sprayed with a 3%
Potassium Nitrate solution just after the flowers have set fruit.
The only time rambutan trees are pruned is at the harvest, when the bunches
of fruit are cut away along with a little wood. This will encourage new
growth from the cut end with the possibility of a second crop that season.
If the fruit are picked individually, a second crop has no chance. The
timber in the branches is particularly weak and careless climbers can
break off large limbs in their hunt for fruit. For this reason you should
use a pole picker to harvest bunches of fruit. This can be made from a
pair of secateurs with one handle attached to a bamboo pole, with a cord
running from the ground through a pulley on the fixed handle, then to
the other handle. Pull the cord to cut off a bunch of fruit.
For the moment, all locally grown fruit is sold in Samoa, but there is
a possibility that this fruit can become an export crop. Research is presently
underway to help this decision, but no definite answer will be available
for 3-5 years. If this does happen, then expect the price to rise rapidly,
so enjoy them while they are affordable in the markets.
Grafted trees, and more information, are available at Nafanua Horticulture
The rambutan season is sadly drawing to a close but if you missed out
on tasting these delicious morsels don’t fret too much. A second,
smaller, crop is on its way and should be ready around June. This season
has been the first one for growers who have cared for their trees for
around 5 years. Prices at Fugalei market of $4 – 6 a kilo have made
their wait worthwhile.
The MAFFM Fruit Tree Project team have had an exciting time over the
past month or so sending some trial shipments of these fruits to New Zealand
for market testing and to see how difficult it is to gain the approval
of the NZ Quarantine service for importing this fruit. The good news is
that NZ consumers enjoyed the fruit at least as much as Samoans do here,
but they are willing to pay much higher prices, making the fruit a good
prospect for export. The bad news is that there is still a lot of pest
control work to be done in ensuring that the fruits sent to NZ are completely
clean of insect pests.
MAFFM researchers have been working flat out over the harvest season
testing many of the varieties of rambutan to prove to NZ Quarantine (and
others) that the local fruit flies are not attracted to these fruits.
This has involved breeding thousands of the flies in sealed cages and
then exposing hundreds of the fruits to the flies when they are ready
to lay eggs. The exposed fruit, which may have eggs inside, are then taken
to another cage where they are left to allow any eggs to develop. When
the larvae hatch from their egg, they leave the fruit and drop into a
sawdust layer where they can be collected. Not one fruit has so far produced
one larva although the trials are continuing, as there are around 8 varieties
of rambutan, each of which has to be tested.
The problem pest is proving to be mealy bugs infesting the fruit. They
do little damage, but there are some that are common here and not in NZ.
The NZ government therefore insists that every mealy bug be removed from
the fruit before they are shipped. They are easily recognised by the white
hairy patches on the fruit, but not so easily removed. They are controlled
on the tree by sprays of oil or soapy water, but this doesn’t remove
them well enough for a quarantine standard. We have to find a safe-for-man-and-fruit
cleaning process that will kill every possible mealy bug on every fruit.
Work is continuing.
Another issue to be dealt with is that having identified rambutan as
a strong possibility for an export crop, there are simply not yet enough
trees in the country to allow an industry to become established beyond
supplying the local market. Rambutan grow to be big trees and need a lot
of land if they are to be grown commercially. Twenty trees, needing 2000
square meters, would be a minimum number to allow a reasonable return
to a household using it’s own labour. An operation employing labour
would need around 200 trees for a worthwhile return on the investment.