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Potatoes Australia August/September 2016
previous crops or pastures;
for example, sulfonylureas
(LOGRAN, Ally) or clopyralid
(Lontrel). These are widely
used on cereal crops and the
residues of these herbicides can
be very persistent in the soil.
Potato crops are also
susceptible to a number of
herbicides that are either not
registered for use in potatoes or
can be affected by spray drift
from herbicides applied to
areas nearby. Therefore, it is
important to consider what
crops or pastures may be near
the site you have selected to
During this slightly quieter
period, for the majority
of processing potato growing
regions, it is timely to start
planning the next season’s
crop. Some of the important
decisions that you should
consider in regards to site
selection are listed below.
Ideally, the area selected
should not have had potatoes
or Solanaceous crops including
tomato, pepper, eggplant or
Solanaceous weeds, such as
nightshade, growing in the area
for the last five years if possible
to reduce disease carryover.
Potatoes prefer soils that are
well-drained, friable in texture
and not prone to periods
of waterlogging. The soil is
a reservoir for water and
nutrients through which air
exchange between the soil
and atmosphere must readily
occur. If the soil is prone to
waterlogging, then the roots
system of the potato plant will
be starved of oxygen, preventing
the potato from being able to
efficiently absorb either water
or nutrients. It also won’t be
able to prevent diseases that
are associated with waterlogged
roots such as Pink rot.
Potatoes can generally
tolerate a low soil pH range
(between 5.5 to 6.5) however,
if the soil pH is less than 5.5 (in
water), soil and plant aluminium
levels may increase and limit
yield and the soil pH could
be adjusted (e.g. with lime).
Be warned that if Common
scab (Streptomyces scabies)
is a potential threat, you may
want to avoid the use of lime
and fresh animal manures.
Instead, try to maintain the
soil pH between 5.0 and 5.2
(applications of sulphur have
proved useful in reducing
the level of scab in some soils
of high pH).
Potato crops can be quite
sensitive to damage from
herbicides that carryover from
grow your potato crops.
Be very mindful in the
growing season of sprayer
tank contamination which can
also cause significant
damage to your actively
growing potato crop.
So, with these important
decisions to make and
considerations to cover when
selecting your growing site, it’s a
good time to think about these
during the slower period of the
season to ensure you are in the
best position when the season
kicks off again.
with Scott Mathew
Ask the industry
THERE ARE
SEVERAL FACTORS
TO CONSIDER WHEN
CHOOSING A SITE
FOR THE NEXT
SEASON’S POTATO
CROP. SYNGENTA
TECHNICAL
SERVICES LEAD
SCOTT MATHEW
EXPLAINS HOW
GROWERS CAN
GET THE BEST OUT
OF THE NEW SITE.
For more information or to ask a question, please contact your local
Syngenta Territory Manager, the Syngenta Advice Line on 1800 067 108,
visit or email Potatoes Australia:
Please note that your questions may be published.
The R&D content for this article has been provided to Potatoes
Australia to educate Australian potato growers about the most relevant
and practical information on crop protection technologies and their
on-farm applications.
This communication has been funded by Horticulture Innovation
Australia Limited using the Fresh Potato Levy and funds from the
Australian Government.
Project Number: PT15007
i
Site selection is key – make sure the soil type is right for the crop.