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It’s that time of year again, so make sure you have your fertiliser sorted for your silage and hay crops. Outgro’s Vegetative Foliar treatments are a great way of getting nutrients into the plant following a pasture harvest. The treatments are fully customisable to suit your soil and herbage needs to ensure you can get that second or third cut this year. Contact us today for a quote.

Lime
The use of finely ground lime (limeflour) is popular in New
Zealand and around the world but the physics and
chemistry is often misunderstood. The expectation in soil
science is that limeflour has a similar level of pH lifting
ability in the long term as the same weight of coarser
AgLime. The clearest difference though is in the speed of
reaction and the significance of that is not just a matter of
patience or even speed of return on investment. It comes
down to an impact on the soil solution calcium and pH
levels in the short term rather than the whole soil pH effect
in the long term.

A small amount of limefour provides temporary changes in
the soil solution that can lead to long term benefits in the
pasture. One aim is to boost clover establishment, clover
nodulation and clover nitrogen fixation. A further aim is to
provide a boost to biological activity that stimulates the
decomposition of organic matter in the soil, improving
nutrient cycling. This can all lead to a pasture response and
the setting up of conditions for improved pasture condition
and productivity in the medium and long term.

Phosphate Rock
Reactive phosphate rock (RPR) is deemed reactive enough
to be used as fertiliser but the speed of release can be over
a period of three or so years depending on conditions.
Being insoluble in water, RPR avoids the issue of flushes of
excess available phosphate such as surface runoff losses,
excessive immediate plant uptake (which could increase
dung transfer losses) and an impact on beneficial
mycorrhizal fungi (which increase root efficiency for uptake
of phosphate, other nutrients and water). Finer grinding of
RPR is one of the surest ways of speeding up the release of
phosphorus in the soil from this natural mineral while still
retaining RPR’s environmental and soil biology benefits.
Plant uptake of phosphate relies on close contact between
the phosphate source and either the plant roots or
mycorrhizal fungi associated with the roots. Finer particles
allow a more even distribution of the phosphate source in
the root zone aiding access to phosphate.

Other Additions
A fluidised blend can provide an opportunity to apply
legume seed to take advantage of the fine lime and trace
elements can also be applied with the benefit of some foliar
uptake. Foliar uptake of most trace elements (and
particularly iodine, copper and cobalt which can be
inefficiently taken up by roots) is more efficient that
application to the soil.
– Dr Tim Jenkins (printed with permission).

Urea through the Foliage
Urea is a particularly efficient form of nitrogen for
foliar uptake since the urea molecule can pass
through all leaf surface channels. Research has
shown that urea is rapidly taken up and once inside
the leaf is safe from volatilisation losses that
otherwise limits nitrogen response. The enzyme
urease operates naturally within plant shoots and
converts urea into available ammonium. That’s
exactly the form of nitrogen required for synthesis
of proteins and other essential compounds. And the
ammonium is in exactly the right place – in the
shoots of the growing plant. Uptake through the
leaf avoids the lag of uptake from the soil and
avoids the nitrate phase (the main form of nitrogen
uptake for most plants) during which leaching
losses may occur and from which the plant must
convert the nitrogen back into ammonium at great
cost to plant energy.

Trace Element Time
Foliar application of urea is a perfect opportunity to
deliver other elements and growth promoters that
can work synergistically with nitrogen uptake.
Trace elements can be added in small, low cost
amounts for the benefit of plant growth and animal
nutrition. Some such elements are much more
efficiently taken up through the foliage than
through the soil matrix. For instance soil uptake of
copper can be restricted by high pH, high organic
matter, and high levels of phosphorus, sulphur and
molybdenum. Foliar application of copper bypasses
those potential issues.

Another trace element, iodine, is essential for
animal nutrition and can be efficiently delivered to
plant foliage (even into fodder brassicas which can
otherwise challenge animal iodine nutrition). In
comparison, application of iodine to the soil is
generally ineffective at improving plant levels.
– Dr Tim Jenkins (printed with permission).

Our comprehensive end to end service provides you with an efficient and quality fertiliser program customised to your farms needs. We pride ourselves in providing you with high quality fertiliser products, in-depth testing and analysis and great customer service from our qualified consultants. Call us today 0800 OUTGRO to talk to one of our consultants.