Iron deficient lawn? Tips on using Liquid Iron fertiliser on your lawn

Author: Adam Fitzhenry   Date Posted:3 August 2022 

Who doesn't love a lush green lawn that neighbours envy and people give a second glance? If your lawn is looking worn and a little yellow, it could be time to get out the iron.

Let’s be honest, coming home to a brown patch of dead grass is less than ideal, and most of us would prefer a lush, green and healthy lawn! If your lawn is looking a little tired and yellow, it could simply be a case that it needs an iron.

Why do plants and lawns need iron?

As iron is a vital micro-nutrient required by plants to form chlorophyll, which is what gives plants and lawns their green colour, lawns and plants need iron. An iron deficiency will occur when there is not enough iron in the soil or it is tied up and unavailable due to a high pH (alkaline soil), or poor aeration. It can also be caused by an excess of calcium in the soil or over application of lime.

How to identify iron deficient plants and lawns.

In most cases, an iron deficiency is easy to spot. Your lawn or plants will have a yellow or speckled appearance. You might also notice the veins of the leaves will be dark and yellow in between.

What to do if you suspect your lawn is iron deficient

First up, check your soil pH. A pH level that’s too high or low can often lead to iron being unavailable to plants and lawns. In the pH is greater than 7.2, the iron present is most likely solidifying and is locked up in the soil. If the reading is normal, it could mean too much phosphorus is present.

How to treat iron deficient lawns

If you find your lawn is iron deficient, it is treatable, and you can DIY. However, the solution does depend on the cause of the issue.

If the cause is a soil pH that’s too high, the remedy won’t be so simple. Products like humic and fulvic acid (and other products) might help buffer or unlock some of the tied-up nutrients to help temporarily resolve the issue and turn the yellow to green, but this will only last a few weeks before returning to its former state. For a long-lasting result, you will need to alter the soil pH.

If your lawn is simply lacking iron, you will need to use an iron product. Our Liquid Iron with Sulphur will help correct iron deficiencies in your lawn, plants and crops, while producing a rich green colour in leaves and the added Fulvic Acid will ensure a quick uptake of the nutrients to provide fast results. However, this product can’t be mixed with other liquids.

How to use Liquid Iron fertiliser on your lawn

When using Plant Doctor’s Liquid Iron, you should avoid mixing with other products, except for Stimulizer. If you’re using with a sprayer nozzle and want to avoid blockages, we recommend applying the iron separated to other products.

When applying to turf and lawns, mix 150-400ml for every 100m2. This product does provide a highly available form of liquid iron with Sulphur, and it can be applied to the leaves or directly to the soil.

Plant Doctor's Liquid Iron is supercharged with Fulvic Acid and is designed to help correct iron iron deficiencies in lawns, plants and produce. 

Liquid Iron can stain paths, paving and skin, so take care when applying near concrete and don’t use during hot weather. Plant Doctor’s Liquid Iron doesn’t need to be watered in however, some people do prefer to water it in, so it comes down to personal preference.

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