Struggling with yellowing leaves or dull, patchy grass? Plant Doctor Liquid Iron Fertiliser is a powerful iron-rich solution enhanced with Fulvic Acid for rapid uptake and visible results. It revives pale, iron-deficient plants by boosting chlorophyll production, helping lawns and gardens bounce back with deep, lush colour. Whether you're rescuing a tired lawn or restoring vigour to fruit trees and ornamentals, this easy-to-apply liquid gets nutrients where they’re needed, fast.
Use Liquid Iron when your lawn or plants show yellowing with green veins, have lost their green shine, aren’t responding to fertiliser, or need a fast colour boost, especially after heavy lime use or in alkaline soils.
Nutrient Profile:
Functional Additives: Fulvic acid (bio-chelating agent) – improves uptake efficiency and translocation and Liquid carrier designed for foliar + soil absorption.
Why choose Liquid Iron:
*Always do a quick “jar test” for compatibility before mixing. Compatible with most humic/fertiliser blends
(LIR)
Iron is essential for chlorophyll formation — the green pigment that drives photosynthesis. But in many Australian soils, iron gets locked up due to high pH, compaction, or excessive lime.
This formulation contains:
The result? Fast correction of iron chlorosis (yellowing), deeper green foliage, and improved photosynthetic function for overall healthier growth.
IMPORTANT NOTE: Iron products can have an adverse reaction with our darker liquids. To avoid blockages in sprayer nozzles, we recommend applying the Iron separately from other products. (Stimulizer is safe to mix with Iron). If attempting to mix together, try a jar test in the ratios you want to apply them in first. Iron should always be added last, after all other products are diluted with water.
Applied separately at various frequencies allows you to tailor nutrient input based on the soil/plant/lawn's requirements and condition.
| Application Type | Rate: | Frequency |
|---|---|---|
| Minimum dilution rate: | 1:50 | |
| Turf: | 150-400ml/100sqm 1.5-4L/Ha |
Apply every 4 weeks in growing season or as required |
| Ornamental Plants: | 10-25ml/10litres water 100-250ml/100sqm |
Apply every 4 weeks in growing season or as required |
| Vegetables: | 150-300ml/100sqm 1.5-3L/Ha |
Apply fortnightly or as required |
| Trees, Fruits, Nuts & Grapevines: | 150-300ml/100sqm 1.5-3L/Ha |
Apply every 6-8 weeks or as required |
| Broadacre Crops: | 3-8L/Ha | Apply as required with normal program |
Not sure how much to apply for your lawn or garden area? Use our Plant Doctor Product Rates Calculator to get the correct rate tailored to your size and conditions.
Do not spray in hot weather conditions. Not compatible with many products. Check the labels and do a jar test first. Iron can stain paths, concrete, paving, clothes, and skin, so always wear old clothes, wash hands after use, and be careful when applying near concrete and paths, etc. Wash off immediately any lasting damage. Keep away from water sources such as ponds, pools, etc. Safe for children & pets when dry. Iron deficiency in many plants & lawns is an indication of high pH or alkaline soil. If yellowing persists or returns rapidly after treatment, soil pH should be checked and adjusted if necessary. Follow application directions as excess liquid iron can lead to other problems, such as zinc and manganese deficiencies. While liquid iron provides immediate relief for plants & soil, it is not an adequate long-term solution for an iron deficiency. Keeping plants/lawn in well-drained soil amended with sulphur to reduce the pH level can help iron in the soil become more available to plants.
Liquid Iron doesn’t have to be watered in, although some prefer to water it in. Either approach is acceptable. Environmental factors such as time of day, wind, rainfall, soil pH, and leaf contact duration can all affect how well Liquid Iron performs. For best results, apply in calm, dry conditions and avoid mowing immediately after application.
Liquid Iron should not be mixed with other products, except for Stimulizer. Mixing it with fertilisers or foliar sprays may cause chemical reactions or reduce product effectiveness.
Application frequency can depend on your grass type, climate, and soil conditions. Many lawn lovers use it every 2–4 weeks during the growing season to maintain deep green colour and correct iron chlorosis. Always follow label guidelines and adjust based on lawn response.
Look for yellowing leaves with green veins (a condition known as interveinal chlorosis), stunted growth, or a dull, pale lawn colour. These symptoms often indicate that your soil is lacking available iron, especially in alkaline soils or after heavy liming.
Yes, Liquid Iron is suitable for lawns, ornamentals, shrubs, and fruit trees. It helps correct iron deficiencies and enhances foliage colour across a range of plant types, not just turf.
When used as directed and allowed to dry before re-entry, Liquid Iron is safe for use around children and pets. It’s always a good idea to keep them off the treated area until the lawn is dry.
Early morning or late afternoon is ideal to avoid leaf burn from midday sun and improve absorption. Avoid applying if rain is expected within a few hours.
If your lawn remains yellow despite regular fertilising, it may be suffering from iron deficiency, especially if the soil is alkaline or compacted. Liquid Iron provides a fast-acting source of iron that can restore colour within days.
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First time owning lawn. Gave the team at plant doctor a ring and they supplied me with a wealth of information. Products turned up quickly.
Will definitely be getting more 8 weeks difference been using stimulizer, activ8mate, soil wetter, seaweed secrets and champion fertiliser. Was super fast delivery.
Only have great things to say about Plant Doctor. Organic products and a competitive price, fast shipping and easy to contact with questions. Have had great results with the special mix for lawns, and my plants (indoor and outdoor) love the seaweed secrets. I am excited to test out some of the animal products soon!
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