In article , david@abacus-
nurseries.co.uk says...

On 15/04/2016 16:20, Chris Hogg wrote:
On Fri, 15 Apr 2016 11:10:54 -0400, S Viemeister
wrote:

On 4/15/2016 10:43 AM, Chris Hogg wrote:
On Fri, 15 Apr 2016 14:45:44 +0100, "Dan S. MacAbre"
wrote:
A level standard teaspoon holds 5ml, which
will be about 5g of ammonium sulphate, so three level teaspoons per
sq.metre will be roughly right.

Are you quite certain on that measurement? 5ml of _water_ weighs 5g -
but I'd be surprised if 5 ml of ammonium sulphate does.

I'm assuming that the ammonium sulphate is loose packed, so would have
a lower density than the pure solid. As a rough check, 5ml of loose
potassium chloride weighs 5.5g. Within the accuracy needed for such
things (it's not analytical chemistry, after all) assuming a
loose-pack density of 1g/ml is probably quite good enough.

I note also that Jeff recommended a similar amount, although he did
say three slightly heaped teaspoons.

I really would weigh it out to start with I have several teaspoons here
all of which are different sizes. So unless you want to use kitchen
spoon measures................

I weigh one measured dose on the scales in a little plastic cup (from
liquid laundry detergent) and mark the cup with a felt-tip to show
where the measured dose came to.

Subsequent measures don't need to be weighed; just fill the cup to the
mark.

Janet.