deficiency is a very common problem in many Australian gardens
and can cause some serious problems to plant health and
vigour. One of the most common and noticeable symptoms of
iron deficiency is a pale green leaf. Following are three
distinct signs of iron deficiency;
Yellowing of younger leaves
Leaves turning pale green to yellow
Leaf veins will remain a darker green colour in contrast
to the rest of the leaf.
If you have plants in your garden or pots that are showing
these 3 symptoms, then you could very well have iron deficiency
Iron is essential for plant growth and also disease resistance.
Iron can be lost from the plants roots in cases of excessive
watering or long periods of rainfall and soil saturation,
but the most common cause of iron deficiency is from the
Iron is very available to plants from the soil when the
soil pH is about 6 and below. As the soil pH increases,
the iron becomes increasingly "locked up" in the
soil and unavailable to plants. If the pH increases over
7, and becomes alkaline, the iron in the soil becomes virtually
unavailable. (Soil pH is calculated on a scale of 1-14.
The lower the pH value, the more acidic the soil. A pH of
7 is considered neutral and above 7, the soil becomes increasingly
All plants need iron to grow, but some plants have a higher
need for iron and can easily show signs of iron deficiency.
These include Azaleas, Camellia, Gardenias, Hydrangeas,
Philodendrons, Roses, Citrus and Fruit Trees, some Australian
Native plants and lawns. Some plants are known as "Acid
loving plants", and this is because they have a high
demand for Iron.
Correcting Iron deficiency is easy and highly successful.
The first method is to apply Searles® Iron Chelate (pronounced
"Keelate"). Iron Chelate is an excellent source
of instantly available iron that can be applied to both
plant leaves and the soil. The beauty of Iron Chelate is
that it will not "lock up" in the soil, so it
is effective in correcting and overcoming iron deficiency
even if the soil has a high pH. You may need to repeat applications
every few weeks until the 3 symptoms as detailed above disappear.
Iron Chelate is a soluble powder that is dissolved in water.
It is easy to apply and gives fast results
other way to overcome iron deficiency is to lower the soil
pH. This is recommended if the pH is 7 or above, especially
if you are growing acid loving plants. To do this, use Searles®
Sulphur Powder. Sulphur Powder is a bright yellow fine powder
that needs to be incorporated into the soil. If you have
established plants, you can lightly rake the Sulphur powder
into the soil surface and cover with a high quality mulch,
then water in. Sulphur powder gradually lowers the soil
pH and may take about one month for full effect.
If your plants have a severe case of Iron deficiency, and
the soil pH tests to be above 7, then you may need to use
both methods together.
Correcting Iron deficiency in the garden is easy and once
this has been done, your loved plants will delight you with
deep green leaves and vibrant growth.
Happy Gardening with Searles from the Searle family.
© Copyright 2002 JC &
AT Searle Pty Ltd
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