How to Revive a Thin, Patchy Lawn – Spring Renovation & Overseeding Advice
Looking for some advice on where to go from here with my lawn.
I’m in Wellington and it’s gradually gone downhill over the last 12–18 months (once was lush and thick!)
A bit of history:
Originally a predominantly perennial rye lawn.
Before last spring’s renovation, I noticed the back area had thinned out after we were away for 5 weeks. I later discovered an outdoor tap had been dripping the whole time, so I suspect that area stayed too wet leading to moss also (third photo taken September 2025 – have since trimmed hedging)
Last spring I hired a scarifying machine which was a petrol one in hindsight, it was probably overkill for a lawn this size and I think I went a bit too hard
I overseeded with NZLA ETF instead of going back to rye. It didn’t establish particularly well at first, which wasn’t helped by some unexpected heavy rain straight after seeding.
I ended up doing a couple more overseeds over summer, and the ETF eventually established.
To level some low spots in the corner, I used topsoil rather than my usual lawn mix. I’m wondering if I applied it a bit too thick in places or whether it settled/compacted differently.
Other factors:
Lawn slopes downhill into the corner.
Soil doesn’t seem fantastic and may be compacted.
Looking at the photos, what would you tackle first and when? Plan is to over-seed in Spring but wanting to know what else can be done to revive the lawn both method and product…
Thanks in advance
Hi Marek, sounds like you've got a good understanding of what you're doing but just need some confidence around dealing with it.
Since you suspect compaction, I'd get hold of a NZLA Core Aerator (or petrol core aerator depending on your total lawn size) and give your entire lawn some good core aerating especially where it slopes into the corner, to help with drainage. Do the core aerating mid-September.
I'd deal to the moss now with NZLA Moss so it's dead and gone before you do any sort of lawn renovation.
Come late September (or whenever soil temperatures are getting close to 15°C @ 10cm @ 6am), give the lawn a light dethatch to remove the dead material and to expose the soil. See if you can borrow/hire a battery scarifier -they do a fantastic job.
Topdress with sand or lawn mix, toss some more ETF seed down, roll it in and drop a good amount of NZLA Starter granular fertiliser down. Keep it consistently damp!! -this is super important with ETF.
Have a read up on NZLA Meso. It's a great pre-emergent to use at seeding.
@Ben Wilton thanks for taking the time to provide feedback. Lawn size is <50m2 so all manageable. Have got an aerator and I think battery scarifiers now available for hire in Wellington (the petrol beast was too much!)
Outside of fert which I have (NZLA starter), Any other products I can use to improve drainage?
Also, any idea what’s caused the brown patches?
@Marek M nice! That's a very manageable size.
You could look at NZLA Penetrate. I've not used the product but its purpose is to drive water away from the soil surface. But a good core aeration should help.
The cause of the brown patches...that's a tricky one. Have you ever treated for grass grubs? Could be grub damage although the damaged looks too blanket for it to be that.
I have not treated for grub damage. Cannot see any evidence of that. Feels like grass just died off. Potential that granular fert wasn’t watered when applied mid-July prior to going on holiday. Was meant to rain that afternoon so didn’t soak but forecast let me down….. or applied too late….??
Is there anyway to tell if grub damage or just grass killed off? Attached new photo on wet welly day after raking leaves and debris…..
@Marek M Do a spade test and have a look in the soil. They will be 20-30cm deep this time of the year though. You can apply a preventative application of Grub+ In late September . I do this every year, the price of it nowadays makes it a no brainer. A few years ago you couldn't access it in small amounts like you can now. NZLA have it in 100ml pack sizes and it covers over 650m2.
https://www.newzealandlawnaddicts.com/lawn-tips/lawn-pests/
@Jonny Hicks thanks mate. Could not see anything with the spade test but will go with preventative.
Other than moss kill, top dress, lawn seed and starter fert, anything else I can do to revive the lawn?