Iron Sulphate Guide
Get fast results with Iron Sulphate
This is the most complicated part of the pack but once you work through it once it will become easier. It is okay if you aren’t 100% accurate but don’t massively exceed the heavy dosage or your lawn can turn black. The best way to calculate it is to:
- Work out the total dosage you need (in grams) based on the Dosage Options below and your lawn size.
- Choose an application method (pressure sprayer ideally or a watering can with a fine rose head)
- Input your total dosage into your application method's Dilution Rate to figure out how much water you need.
Dosage Options
- I have moss: A high dose (5g per SQM) will do all the previous benefits but is also known to blacken any moss infestations. If used at a high dose make sure to rake or scarify the lawn 14 days after application.
- I don't have moss: A medium dose (2.5g per SQM) will 'green-up' your lawn rapidly and harden it to make it more resistant to disease.
Dilution Rate
Mix well with lukewarm water using the rates below:
- High dose (5g per SQM) dilution rate
- Watering can: 10g per 1L of water
- e.g. Divide your total dosage of iron by 10 to get your water requirements in litres.
- Pressure sprayer: 20g per 1L of water
- e.g. Divide your total dosage of iron by 20 to get your water requirements in litres.
- Medium dose (2.5g per SQM) dilution rate
- Watering can: 5g per 1L of water
- e.g. Divide your total dosage of iron by 5 to get your water requirements in litres.
- Pressure sprayer: 20g per 1L of water
- e.g. Divide your total dosage of iron by 20 to get your water requirements in litres.
Application
- Must be applied evenly or it can create black patches on the lawn. For this reason avoid walking across areas you've just applied it to.
- Be careful about getting it on any patios or inside as it stains hard surfaces very easily. If this happens, wash and scrub surface immediately.
When To Apply
- Medium doses: can be applied at 4-week intervals, at least 8 weeks after seeding.
- High doses: can be applied at any time as long as it is at least 8 weeks after seeding. Typically applied 2 weeks before seeding to blacken moss ready to rake out.
Example Calculations
Dilution/Dosage Example Tables
Moss Control (high dose)
| Lawn Size | Iron sulphate (5g per SQM) | Water (watering can - 10g/L) |
Water (sprayer - 20g/L)
|
| 50sqm | 250g | 25L | 12.5L |
| 100sqm | 500g | 50L | 25L |
| 150sqm | 750g | 75L | 37.5L |
| 200sqm | 1000g | 100L | 50L |
| 250sqm | 1250g | 125L | 62.5L |
Green-up/disease resistance/turf hardening (medium dose)
| Lawn Size | Iron sulphate (2.5g per SQM) | Water (watering can - 5g/L) |
Water (sprayer - 20g/L)
|
| 50sqm | 125g | 25L | 6.25L |
| 100sqm | 250g | 50L | 12.5L |
| 150sqm | 375g | 75L | 18.75L |
| 200sqm | 500g | 100L | 25L |
| 250sqm | 625g | 125L | 31.25L |
Calculation Examples
Low/Medium Dose Dilution Rate
Watering cans: 5g dissolved into every 1L of water.
Sprayers: 20g dissolved into every 1L of water.
Calculation for a High Dose in a Watering Can Example:
10 SQM = 50g of Iron Sulphate mixed in 5L of water
50 SQM = 250g of Iron Sulphate mixed in 25L of water
Calculation for a High Dose in a Sprayer Example:
10 SQM = 50g of Iron Sulphate mixed in 2.5L of water
50 SQM = 250g of Iron Sulphate mixed in 12.5L of water
Using Iron Sulphate with The Lawn Pack? You have 2 options:
Option 1: Use a high dose 2 weeks before applying The Lawn Pack. If your lawn has a very thick layer of thatch then scarify first.
Option 2: Use a medium dose after your new lawn is fully established (week 8) and again when desired (wait at least another 4 weeks).
Please get in touch if you are not sure about any of the above.