2015 Lawn thread

[RichB]

jagnet said:

From the other photos it does look as though shade could be a big issue for your lawn? Does the lawn suffer from poor drainage, and is there a chance that it could have been over watered?

Shade is indeed a huge issue and I do try to fork it and top dress it. I doubt it's overwatered.

[jagnet]

I would overseed with something like Lawnsmith's Shadygreen and keep the cut higher than it looks in the photos. Lawnsmith suggest 1 to 1.5 inches in normal use, and 2 to 3 inches in times of stress.

For a ryegrass free shady mix that can withstand some wear Germinal's A6 Supreme Shade with Poa supina is a good alternative and should tolerate dry conditions better so may save on watering.

Shady, sheltered lawn areas are tough to deal with and regular over seeding to maintain sward density and help combat moss and weed invasion is pretty much a necessity no matter how much care you give the lawn. A higher cut and regular, but not excessive, feeding really helps.

[RichB]

Thanks... must confess I had started cutting it closer because I thought it might weaken the coarse grasses.

[Dr Mike Oxgreen]

RichB said:

Thanks... must confess I had started cutting it closer because I thought it might weaken the coarse grasses.

That's exactly what I was doing earlier this year - I thought I was combatting Yorkshire Fog, and close mowing would hurt that. But I've changed my mind and now believe a lot of my coarse grasses might be annuals like crabgrass or Poa annua, in which case I'm not convinced that close mowing helps. I find all these weed grasses too difficult to tell apart - they all just look thick, coarse and ugly, and their appearance can vary a lot depending on growing conditions and mowing regime, so they never quite look exactly like they do in a book.

I gave up mowing close because it was making the lawn look tired; I returned to a slightly higher cut.

I just can't wait to glyphosate the hell out of it all and start from scratch. We go away on holiday in just over a week's time, so I'll be doing it just before we go. It's going to be very cathartic, but I reckon scarifying up all the dead grass is going to be a big job!

[jagnet]

An interesting breakdown of nutrient loss through grass clippings from the makers of Primo Maxx landed in my emails this week via Pitchcare:


source

Whilst Primo Maxx is a rather expensive proposition for the average domestic lawn, it does show that quite a lot of N and K can be returned to the lawn by reducing clipping collection and letting the clippings decompose in situ where possible.

[R8VXF]

I haven't collected clippings since I redeemed and the lawn is looking fantastic. Couple that with timed early morning watering, and it is all I can do to keep on top of the mowing!

[jagnet]

This is really the first year that I've been leaving the clippings much more often than not and chemical fertiliser use does seem to have been less, although direct comparisons with previous years are somewhat tricky due to so many other variables.

I did find this 1970s study - Clipping disposal investigation with rotary lawn mowers. It's interesting just how quickly the nitrogen was made available to the grasses after cutting (14 days), and how much extra fertiliser was required on those areas where the clippings were collected to maintain the same level of growth and colour as those areas where they weren't collected (8 pounds v 6 pounds of nitrogen per 1000 square feet).

It does still feel a little strange not collecting the clippings though.

[moles]

Barny can you not see the clippings on the lawn I know you said you mow 3 times a week but even so with watering I'd imagine the clippings are 10-15mm long do they not show on the lawn at all?. How low are you cutting the lawn with the classic seed?.

[Dr Mike Oxgreen]

Last year I left the clippings on the lawn almost every time I mowed. It does work much better if you're mowing very frequently (twice a week), then the clippings are short enough that they don't really show. I don't have a mulching mower though.

But if you leave it any longer then the mower will start depositing the clippings in clumps, which will cause the grass underneath to go yellow if left. To a certain extent these can be chopped up and redistributed by going back over them with the mower.

This year I've been collecting all the clippings and processing them in the HotBin composter, which composts at temperatures up to 70C and produces compost you could use for mulching in 2 weeks.

[jagnet]

Dr Mike Oxgreen said:

This year I've been collecting all the clippings and processing them in the HotBin composter, which composts at temperatures up to 70C and produces compost you could use for mulching in 2 weeks.

With a turnaround time that fast I imagine that you're going to lose very few if any nutrients to leaching, and most weed seeds are going to be suitably cooked at those sorts of temperatures. That's definitely an advantage over my cold composting arrangements, where the compost piles do their thing over a 3 year cycle. The only thing that puts me off the HotBin is the price - ouch! If I was starting from scratch it'd likely make more sense taking into account the cost to build the cold compost bins, but then I'd still need somewhere to store the pre and post production materials.

[R8VXF]

moles said:

Barny can you not see the clippings on the lawn I know you said you mow 3 times a week but even so with watering I'd imagine the clippings are 10-15mm long do they not show on the lawn at all?. How low are you cutting the lawn with the classic seed?.

They generally disappear from view in a day or so, I just go round and make sure any large clumps are redistributed. Currently mowing on setting 4 of 5 on the mower.

[Willeh85]

Thought I'd post an update to my lawn attempts 4 months after I did all the hard work. I experimented with what the best cutting height is for my lawn and it would seem from my last picture that its topping it on 2nd highest and every 4-5 days. I've not done anything chemical wise other than use garden lime at the start of spring to help combat the moss, and I'm quite pleased with the results.

On a side note, yes I'm aware the flowerbeds and rear are a complete mess. I've got some plans for those soon, watch this space.

After forking the whole lot by hand at the start of April


Top dressed and overseed.


The results 4 months later.

[jagnet]

Willeh85 said:

The results 4 months later.

That's a great turnaround; the turf looks so much more consistent and healthy.

On the choice of lime to control moss, was the problem that of particularly acidic soil?

[Willeh85]

jagnet said:

That's a great turnaround; the turf looks so much more consistent and healthy.

On the choice of lime to control moss, was the problem that of particularly acidic soil?

Thanks, its still very bumpy in places but its getting better.

I read that moss likes soil that is more acidic, so I bought a soil tester from ebay to see what my soil was like out of interest. I was quite methodical and divided the lawn into a grid in my mind and tested it in the middle of each square. Quite a few read around ph 6 but there were lots at 5 and one or two that were in the 4 range . So I gave it a dose of lime through a spreader which was about half of a smallish box I got at my local garden centre for about a fiver, and a month later all my moss turned black and I raked it out.

I never actually tested the soil again after that, but if you're interested I can go get some readings again?

[jagnet]

Wow, that's some serious acidity in places then It's no wonder the moss was at an advantage. Liming it was definitely the right move.

Did you test any of the soil in the borders away from the lawn? It'd be interesting to know if that ph level was common throughout the garden or more specifically just the turf area.

I would definitely continue to monitor the situation, aiming to achieve a ph of between 6 and 7.

[WinstonWolf]

Just to be clear as I've got a thatch problem, short clippings are better not collected, if you've not cut the lawn for a week or so put the bucket on and dispose of them elsewhere?

[jagnet]

Yes, if thatch is an existing issue then that really needs to be sorted first so as not to exacerbate the problem. Clippings on top of a thick layer of thatch are likely going to take too long to break down.

[WinstonWolf]

thanks, that's how I'll mow it next year, just making sure the lawn consists of nothing more than grass and soil for the rest of this year

[Dr Mike Oxgreen]

In theory, grass clippings shouldn't create a problem with thatch because if fine enough they should break down in contact with the bacteria in the soil. But I reckon jagnet's right that if you've already got a significant thatch problem then that will prevent the clippings reaching the soil, so they'll sit on top and add to the thatch problem.

Tomorrow evening I'll be glyphosating my lawn. The plan is to scarify and re-seed on the bank holiday weekend - the scarifier is booked. I'm getting peculiarly excited!

Edited by Dr Mike Oxgreen on Monday 10th August 09:55

[sparkythecat]

My thatch ridden lawn is in desperate need of scarifying. Is now the best time or should I leave it a week or two?