Great for my citrus!
I bought this a few months ago and recently sprinkled some over the top of the soil of my potted citrus. They often develop iron deficiency in pots. This slow release product should manage it for longer periods of time.
Iron Sulphate Heptahydrate Powder | For Lawns & Moss Control | Soluble Slow release powder - 4.5kg
19.5% Iron, 11.5% Sulphur
Slow-release ferrous sulphate powder (Fe >19.5%, S 11.5%). Helps correct iron deficiency, deepens lawn greening, reduces moss, and gently acidifies alkaline soils. Longer-lasting soil store of iron when applied to soil or compost.
Iron Sulphate (Fe 19.5% + S 11.5%)
Restores Deep Green Colour
Fixes Iron Deficiency & Yellowing
LawnsGardensFarms
$39.95
Description
Iron (Ferrous) Sulphate Heptahydrate Powder, Slow Release Green-Up & Soil Health
If your lawn, garden, or turf is looking yellow and tired, our Iron (Ferrous) Sulphate Heptahydrate Powder is your go-to for deep, lasting green. It’s slower to act than fast chelate types, but that’s because it works steadily, building a long-term store of iron in the soil that can last for years. Ideal for improving plant colour, reducing moss, balancing soil pH, and promoting healthier, more resilient growth.
Use our Iron Sulphate when lawns show yellowing between leaf veins (chlorosis), in alkaline soils with a pH above 7.0, or when moss begins to invade turf. It’s also effective for boosting plant health without adding excess nitrogen and for long-term soil conditioning.
Nutrient Profile:
Fe
Iron
>19.5%
S
Sulphur
11.5%
Water-soluble ferrous sulphate (slow release iron source)
Why choose Iron Sulphate:
- Deep, rich greening without excessive growth
- Long-lasting results thanks to slow-release form
- Moss control that’s gentler on the environment than harsh herbicides
- Soil pH balancing to unlock more nutrients for plants
- Supports healthy roots, photosynthesis, and enzyme production
- Multi-use for lawns, gardens, turf management, and agriculture
Iron sulphate is specifically for:
- visible deficiency correction
- colour correction (chlorosis)
- soil chemistry adjustment (pH + iron availability)
Transform your lawn or garden into a vibrant green space, naturally. With our slow-release Iron Sulphate, you get lasting results and healthier soil, season after season.
(846)
How it Works
The Science Behind Iron sulphate:
Our Iron Sulphate contains >19.5% Iron (Fe) and 11.5% Sulphur (S) in oxidised form.
- Iron supports chlorophyll synthesis, boosting photosynthesis and leaf greening.
- Sulphur assists enzyme and protein building, and gradually releases small amounts of sulphuric acid, which naturally lowers soil pH.
- Unlike fast-acting chelates, the slow release of minerals means less leaching, fewer applications, and sustained plant health.
Application
| Purpose | Application Rate (g/m²) | Method | Notes |
|---|---|---|---|
| Correcting Iron Deficiency | 20 – 30 | Spread dry or mix with water and spray | Apply the product evenly at recommended rates per square metre. You can either spread the powder directly over the surface or dilute it in water and spray it on. After application, water the area thoroughly to activate the treatment. For ongoing effectiveness, reapply each season or as needed based on your lawn’s condition. |
| Soil Acidity Adjustment | 25 – 35 | Spread dry or mix with water and spray | To help improve soil acidity, apply the product evenly across the soil surface, either by spreading the powder or spraying a diluted solution. Follow with adequate watering. Repeat applications can be made as necessary to maintain optimal soil pH. |
| Moss Control | 10 – 20 | Spread dry or mix with water and spray |
For moss removal, apply evenly to affected areas, watering in well afterward. Application can be done most times of the year, with spring being the common period for treatment. However, more frequent applications every 6 to 8 weeks from late autumn through winter to early spring will help prevent moss growth during those cooler months. For best results, treat the entire lawn rather than only mossy patches, as iron sulphate acidifies the soil and can cause visible differences between treated and untreated areas. |
IMPORTANT TIPS:
- Application Method: Sulphate of Iron is a fine powder generally spread dry, ideally using a broadcast spreader for even coverage and to avoid powder blowing onto unwanted surfaces. It can also be diluted in water and sprayed on. Please note this product does not contain anti-caking agents and the powder can form clumps over time, these are best dissolved in water not hotter than 50`C and sprayed on.
- Safety: Apply on calm days to avoid wind blowing powder. Avoid spreading into the wind. Always wear protective gloves and a dust mask during application.
- Post-application: Water the lawn thoroughly after spreading. Avoid walking on treated areas until they have been well watered in to prevent uneven treatment and staining.
Safety
Safety Guidelines
Keep out of reach of children. May be harmful if swallowed. If eaten seek medical help. ALWAYS TRIAL BEFORE CHANGE. Before a new rate, product or application method is used, a small trial is recommended. Warranty of this material, either expressed or implied, is limited to a guarantee of the composition as shown on this label in as much as uses are beyond the seller’s control. For the same reason, the seller is not liable for any injury to any living thing, crops, soils, or materials which may result from the use or storage of this material. As this is largely a mineral-based fertiliser made from natural resources, the analysis may change slightly. When applying the product, wear gloves, a dust mask, and old clothes to protect yourself, as it can stain paths, concrete, clothing, and skin. Keep pets off treated areas for one week, and horses for four weeks. Avoid spreading by hand on windy days; using a broadcast spreader is recommended for even coverage. If any product lands on paving, sweep it off immediately to prevent staining.
FAQ
What is Iron (Ferrous) Sulphate Heptahydrate powder used for in lawn and garden care?
Iron Sulphate is widely used to correct iron deficiency (chlorosis) in turf and plants, eliminate moss, reduce soil alkalinity (pH), and act as a trace micronutrient in fertilisers. It helps promote deep greening of turf grasses without excessive growth, improving lawn health naturally.
How does Iron Sulphate affect soil pH?
Iron Sulphate naturally acidifies soil through microbial breakdown, releasing sulphuric acid that lowers soil pH. This is beneficial in alkaline soils where iron becomes unavailable to plants. However, overuse can make soil too acidic, so it’s important to follow recommended application rates.
How do I apply Iron Sulphate powder to my lawn or garden?
Spread evenly using a broadcast spreader or mix with water and spray. Recommended rates vary by purpose: 20-30g/m² for iron deficiency, 25-35g/m² for soil acidification, and 10-20g/m² to control moss. Always water in thoroughly after application and avoid walking on treated areas until soaked.
Can Iron Sulphate be used for moss control?
Yes, Iron Sulphate helps control moss by making the soil less hospitable. For effective moss removal, apply 10-20g per square metre every 6–8 weeks from late autumn to early spring and combine with lawn care practices like dethatching and overseeding.
Are there any safety precautions when using Iron Sulphate?
Yes, Iron Sulphate can stain concrete, paths, clothing, and skin. Wear protective gloves and a dust mask when applying, avoid windy days, and keep pets off treated areas for at least a week. Horses should be kept off for four weeks to avoid grazing on treated turf.
How often should I apply Iron Sulphate to maintain lawn health?
Reapply Iron Sulphate every season or as needed based on soil and turf condition. Regular soil testing helps determine the best schedule and amount to use for ongoing lawn health and moss prevention.
Can Iron Sulphate be mixed with other lawn care products?
Iron Sulphate is not compatible with many products and can react adversely. Always perform a jar test before mixing and follow label instructions to avoid clogging or reduced efficacy.
Why should I conduct a soil test before applying Iron Sulphate?
Soil testing identifies pH levels, organic matter, and nutrient deficiencies, helping you apply the right amount of Iron Sulphate safely and effectively. It prevents over-application, which can harm your lawn by making soil overly acidic.
Reviews
customer reviews
Showing newest first
Great product
Got this product to kill out heaps of moss in my lawn. Saw results within a few hours and was able to rake most of the dead moss out of the lawn in the next few days. Will be applying in the next couple of weeks to suppress it and kill the rest. Would highly recommend
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5.0
from 0 verified reviews
Great for my citrus!
I bought this a few months ago and recently sprinkled some over the top of the soil of my potted citrus. They often develop iron deficiency in pots. This slow release product should manage it for longer periods of time.
Verified review
Great product
Got this product to kill out heaps of moss in my lawn. Saw results within a few hours and was able to rake most of the dead moss out of the lawn in the next few days. Will be applying in the next couple of weeks to suppress it and kill the rest. Would highly recommend
Verified review
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