Hi,

I'd like some advice on lawn care.

I have worked hard to try and improve the condition of my lawn over the
last 2 years since I moved to a new house, with only limited success.
The lawn was full of moss and yarrow when I moved in and I have
successfully removed much of this through the use of feed and weed,
moss killer, scarifying, top dressing an reseeding. However, in
May/June last year and once more this year I suddenly seem to hit a
problem where by some 25-35% of the grass (possibly just the original
grass) appears to die (pale yellow/whitish) for no obvious reason. This
obviously makes the lawn look in poor condition which is annoying given
the work put in so far ! So, the question is why should this grass
suddenly die ?

Here's some more detail:

- Tha lawn is well protected from wind and receives sun for much of the
day. It is mostly flat apart from a drop between two levels. I never
water the grass (certainly not needed this year so far).

- In mid April I used feed, weed and moss kill (12% nitrogen). We had
two mild frosts after this application. However, the results after two
weeks were great with the whole lawn was looking extremely green and
growing really well. One issue maybe that I never really new how much
my spreader was putting down (no instructions) hence I may have over
done it, or underdone it ... could this be the cause ? I have a Scotts
Evergreend distributor so if anybody knows what the numbers 1-19
represent that would be useful

- I have a mix of weeds in the garden including clover, yarrow,
germander speedwell plus others. General impression I get is these
weeds indicate a lack of nutrition in the soil.

- There are areas which show up with Red Thread disease, I suspect more
so after all this heavy rain. Does this indicate poorly draining soil
?

- The soil is chalky but not until 10-12 inches. On top of that is soil
which I think has an okay pH, although can't recall exact value.

- Newly seeded grass from this year is growing really well. I have used
standard family hard waring grass mix rather than the finer looking
grass that was already down (although I guess this may have just been
the same grass but poor quality).

- The lawn had been poorly maintained for years prior to us moving in.

- I have never aerated the lawn deeply. Those roll spikers never seem
much good and hand coring for a large lawn is a nightmare !

- I mow 1-2 times a week but suspect I have cut too much grass at times
as I have cut greater than 1/3 off at a time. I have noticed the tops
of the grass have browned, yet I have sharpened the blade twice already
this year. Exactly what is 'sharp' for a mower blade ?

I imagine the issue is general poor quality soil rather than one
specific issue, if that's the general view what's the best way to get
the goodness back in. Extra fertilizer applications, more top dressing,
machine based aeration ?

Thanks for any advice,

jed