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THECOMMERCIAL GREENHOUSEGROWER • APRIL 2018
• HORTICONTACT TOUR
Visitors that attended this year’sDutchHortiContact tour
were rewardedwith a tour of one of the country’s largest
tomatogrowers and apeek behind the scenes of the
newly-openedWorldHorti Center, writesStevenVale.
Some 2,400ha of the roughly 9,500ha of Dutchglass
is found in theWestland, and this beatingheart of the
country’s horticultural sector is home toVander Lans,
whichgrows tomatoes at three sites totalling32ha inDe
Lier. Plus, they have another two sites (total 20ha) in the
southof the country at Rilland, in theDutchprovince of
Zeeland.
Webelieve the largest Dutch tomato areaworks on an
area of 180ha, but family-ownedVander Lans, which is
runbyCees, Vincent, Erwin andLeo vander Lans, is one
of just a handful of growers operatingon an area of over
50ha, and this area is about to increase. The fourmen
recently purchased land to the southof Rotterdamwith
planningpermission for 36ha of glass.When it is all built
(planned sometime 2022) thenVander Lanswill grow
tomatoes onnearly 90ha!
Back to thepresent andwe visited a 10-year-old, 8m-tall
and 9.5ha structure inDe Lier, where the focus is 100%
on cocktail tomatoes.
Right from the start, our guide, Vander Lans staffmember
TOMATOESAND
WORLDHORTI CENTER
Thebumblebeeboxes are closed automatically at the endof
the afternoon.
what actions they need to takewith thebeeswhen
spraying,” addsNeil. “Thiswill normally involve closing,
and sometimes removing, the hives from the greenhouse
andobserving the recommendations onhow long the
bees shouldbe excluded from the crop. It is important if
growers do need to remove the hives that they need to
be returned to the exact sameposition andorientation to
maintain the hive’s efficiency.”
Withhandpollinationbeing expensive, repetitive, time
consuming and sometimes unreliable, there are high
hopes for theAHDBHorticulture fundedproject PE031,
which aims to improve the industry understandingof
poor pollinationperformanceby audax bumblebees in
UK tomato crops. “We are not surewhy some growers
are finding that exclusive use of the nativebumblebee
(audax) is not as efficient aswere thepreviously used
non-natives,” explainsDrMorley. “We arewaiting for the
AHDB report onour BumbleBee survey, and aim to set up
aproject to investigate further.”
DavidFoster, Koppert UKGeneral Manager points
out that their bees arebred tohigh standards and
independently certified tobe free of diseases and
parasites before they aredespatched. “That has always
been the case,” he adds. “There is no contact with the
outsideworldduringproduction.”He alsopoints out that
the small audaxmarket in theUK is currently subsidised
by largeproducers likeKoppert.
Koppert has also conducted trialswithNatural England
at Chichester-based tomatogrower EricWall: “Wedid
extensive studies looking at activity andbrood size of the
different species andwe couldn’t find adifferencewhich
may bedue to the improvementswe’vemade toour
audax over the years,” commentsDavid. “There are lots
of other factors to consider when assessingpollination
performance, including new cultivarswithmore flowers,
the use of thermal screens and the affect of addingnew
hiveswhenold colonies are still in the crop.”
In its positionon commercial bumblebees, whichwas
last updated in June 2016, theBumblebeeConservation
Trust says, ‘The extent of what we know about the
consequences of importingbumblebees is increasing.
However, further research is needed into thedetection
of parasites anddiseases, themeans of sterilisingpollen
fed to commercial bumblebees, the risks of imported
species and subspecies becoming invasive, and the
extent towhich commercial bees have already become
established in thewild. Until producers and legislators can
guarantee that commercial bumblebee colonies donot
carry infectious pathogenswemust takeprecautions to
ensure that commercial importedbumblebees (including
endemicUK sub-species) are not released into thewild.’
Commercial growerswill hope that new researchhelps to
provide suchguarantees.
