Iron sulphate on lawn

[Lee Nowell]

Hi All

I have bought some iron sulphate to help get rid of the moss in my lawn. The manufacturer says I should dilute 2 or 3g of it in 1 L of water per 1m2. The lawn is around 300 M2 so 300L sounds an awful lot. Anyone have any experience of this This is the manufacturer's instructions

Also it isn't clear whether 2/3g is sufficiently strong to kill the moss. Any advice here too please?

Thanks

Lee

[GB]

Can you get something to attach to the hose that will dilute the crystals whilst you spray? That would save carting 300l around.

[brian]

In message [e-mail], Lee Nowell [e-mail] writes

By chance I flushed out a couple of cast iron radiators on the front lawn and the sludge seems to have killed the moss leaving the grass intact. Next time I drain the system, I should keep the drainage and use it to spray the lawn . It won't be iron sulphate, probably ferrous oxide.

Brian

[Jeff Layman]

Don't get the iron sulphate (dry or in solution) on concrete, bricks, paving, wood, or anything else you don't want permanently stained with a rust colour.

You need to consider why the moss is there. Moss grows best in damp, shady conditions, so if the part of the lawn with most of the moss is poorly drained and shaded by trees you are wasting money trying to get rid of it with iron sulphate. It will return in time. You need to ensure the lawn soil is free-draining, and prune back any overhanging tree branches.

Or you could just accept that, like grass, moss is green and requires a lot less maintenance than grass! ;-)

[Andy Burns]

The instructions that came with mine say 10-15g/l and apply at 3l per

10m^2 if that fails re-apply at 20-40g/l

I suspect I started with 20g/l and it worked well

Don't splash any onto wooden fencing, unless you want to stain them black!

[Andrew]

I usually buy 16Kg of ferrous sulphate crystals from Mole Valley Farmers and it is in fine granular form, like castor sugar. I just carefully sprinkle the stated number of grammes per sq metre which I mark out with lengths of redundant alarm signal cable and bits of cane.

It does kill the worms I believe, so you are denying the blackbirds and robins their food source.

[Lee Nowell]

Quick update in case it helps others. I found a Q&A on their website and hidden in there was a question about what to do for larger areas. Seems like the grammes of product per M2 is more important than the amount of water. They suggested using 1/10 for 50m2 to treat the moss. of the water (so 250g for 5L)

[fred]

I had the same problem but over a big area even using a knapsack sprayer I found the dilution solution too tedious so I just sprinkled it on

[Paul]

There is temperature dependent solubility, listed in Wiki for it (right side bar).

So at some point, no additional turquoise crystals will go into solution (heptahydrate).

And that helps determine what the absolute smallest volume of water you could use.

Paul

[Lee Nowell]

Realised yesterday that I sprayed the 5L of solution over 100m2 instead of 50m2. Now waiting to see whether it killed any moss before reapplying. I assume the second one is a top up and therefore should be at 5L per 100m2 rather than a reapplication of 5L over 50m2?

[wasbit]

According to the label on a 1kg tub

Guidelines Grass Greening - 1-2g per litre of water per square metre Turf Hardening - 2-3g per litre of water per square metre Moss Control . - 4-5g per litre of water per square metre