using winter and iron lawn fertilisers

Using Winter & Iron Lawn Fertilisers

Ferrous or iron sulphate is the active ingredient in moss killer and as part of a Winter Feed produces deep green grass with only minimal growth

Option 1: GREEN-UP Soluble Ferrous Sulphate

This is also sold as Moss Killer. It is just a sulphate of iron and as such will cause no growth therefore being an ideal treatment to enhance the lawn without worrying about whether or not conditions are right for mowing.

For lawn and grass green-up apply at 0.5 to 1 gram per square metre in solution - 6 applications can be made with 2 or 3 being reasonable

For turf hardening - aids disease and cold resistance and worm cast suppression apply: at 2+ grams per square metre in solution – up to 3 applications can be made with 1 to 2 being common

For moss - causes blackening: apply at 4 to 5 grams per square metre in solution

  • Up to 2 applications 4 to 6 weeks apart
  • Best applied early before moss becomes too dense. This will retard further growth without too much obvious blackening
  • Can be applied a third time in spring as part of a moss removal program

If you are going to apply at the highest rate and it is the first time you are going to try this treatment I would suggest two applications of 2 to 3g/m²each and space the two applications by a few days. This assists penetration deeper into the moss whilst being gentler on the grass. It also allows you to assess the success of the first application and therefore decide on the application rate of a second application. See Ferrous Sulphate Application for more details.

Warning: The maximum rate for application to grass of Lawnsmith® Soluble Ferrous Sulphate is 5g/m2. Do NOT apply other ferrous sulphate products based on these figures.

Option 2: WINTER GREEN High Iron Lawn Feed

This is a slowly soil soluble high iron granular fertiliser. It contains the moss killing ingredient ferrous sulphate.

Though this is a quick release fertiliser it will act more like a slow release product due to the cold conditions. The nitrogen content is very low making this an ideal product to apply without causing growth in wet or mild winter conditions. Useful to harden the grass against the fungal disease fusarium, for greening, general grass health and adding vital nutrients during wet or mild winters. It will last between 6 and 8 weeks.

For lawn and grass green-up one application @ 20-25 grams per square metre

As a turf hardener (disease and cold resistance) one application @ 35 grams per square metre in late autumn

For moss - up to 2 applications @ 35 grams per square metre - normally one in late autumn and one after 8-12 weeks

Combination Applications

You don't have to use one or the other as both can be used during a season depending on the circumstances. You need a 4-6 week gap between treatments of Winter Green and Ferrous Sulphate. Generally it is best to apply the Winter Green during a mild spell over winter and one application over the winter period is the norm.