Iron 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 problems. 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 soil pH. 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 alkaline). 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 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
The 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 You may make a copy of this Fact Sheet for your personal, non-commercial use only. Please do not make any other use of this Fact Sheet without first obtaining our permission.