Browse Forums Landscape & Garden Design 1 Mar 11, 2015 5:23 pm Hi everyone, I'm looking to get my lawn laid sometime soon with a contractor helping me with excavation. Being in rural victoria, I have called around a few places to have good soil delivered and found this place http://therockyard.com.au/soils/ I'm looking to have 350m2 of lawn and have 100mm of good organic soil( means I need 35m3 yes?) tilled down to 400mm. I chatted to the rep there and she seems to think that the premium mix consisting of mainly organic stuff might be too rich for my clay soil or lawn. Is that true? I have been reading Fu's guide religiously and would definitely want to follow his advice but it's so difficult to find good organic soil around here. Most people just tell me to lay it directly on my clay or with some gypsum/sandy loam which I know will work but is kind of wrong. What do you guys think? Get the premium mix and try it or maybe just go for the lawn mix available? Is 35m3 overkill for a 350m2 area? Regards Khee Lawn/Turf advice 3Mar 12, 2015 9:00 am Hey Kyeo, if you have enough top soil already just till through 1m2 of compost (not soil) to 20-30m2 of existing soil down to 300mm max. Fu's advice is spot on for Perth as it aerated sand so you can till down way easier than we can in clay. So part of his info applies to us.. You need some top soil though.. after most new builds the site is scalped down to the sub soil and in this case its a different approach.. Let me know what you have.. Pics would help. Re: Lawn/Turf advice 4Mar 15, 2015 5:05 pm Hi Beatrix, took some pictures for you First 2 pics are the soil untouched and dry Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ After digging 10-20cm deep, soil still looks the same a bit clayish Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ Last 2 pictures is holding a hose for 20-30 seconds over the soil, it doesn't seem to absorb much water, just flows on top, which is worrying me as I'm afraid it might lead to mild flooding issues. Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ What do you think? Just get someone to excavate and level normally or account for more topsoil to be added to it? Thank you in advance Re: Lawn/Turf advice 5Mar 15, 2015 5:29 pm For your turf to survive and to lessen the amount of water you need to keep it looking good you need a decent amount of topsoil underneath the turf itself. Any added organic matter/soil etc will aid both. All the above comments are good advice. Gypsum as B STAR says will help break up the clay and as BK says too topsoil and organic matter is the way to go. Don't skimp on prep and if you follow the advice in Fu's excellent guide, it will save you a lot of time and effort in the long run. Stewie Re: Lawn/Turf advice 6Mar 16, 2015 6:31 pm Hi Kyeo, Doesn't look like much in the way of good top soil for turf unfortunately. It's a biggish area, so a couple of options. Cheap and easy is to firstly level/escavate the area. Then rip the clay to 20-30cm depth with the escavator. Then rotory mix in compost 1m2 organic compost per 20-30m2 and gypsum* as per directions. Best practice would be to PH test the existing soil and add ammendments as needed. These tests are easy and cheap. Then just plant a Kikuyu grass. Or do as above but just add gypsum to the ripped clay. Then layer a good quality sandy loam turf soil on top - 200mm is ideal. Don't mix them together they are very different soils and won't give you a great result. You will need to add drainage if thats an issue. That clay will still get waterlogged and will runoff even with 200mm of sandy loam on top.. See how you go though and if possibe add it later. Then plant turf of your choice.. The rest of FU's ammendment like perlite/zeolite etc aren't really that proven in heavy clay based soils. The liquid ammendments all work to a certain degree, bit a trial and error for you to find the best ones. *Gypsum - do a soil dispersion test to check if your soil is gypsum reactive. If it isn't don't add it, it won't work no matter what anyone says. http://www.abc.net.au/gardening/stories/s131432.htm Re: Lawn/Turf advice 7Mar 17, 2015 5:26 pm Hi BK thanks for the advice, I'm thinking of adding organic soil to the clay soil as per your advice at this stage , so that will be 350m2 of turf / 30m2 = approx 18m2 of organic soil X 300mm = 5.4m3 worth of organic soil is that correct? Need to run a test on the gypsum at this stage. Lawn/Turf advice 8Mar 17, 2015 6:35 pm Hi there, pardon my calculations were a little sloppy earlier.. But yes you are right 5m3 will do it. So it basically works out to 2m3 of compost per 100m2 of clay soil. Spread the compost 20mm thick then till it through to 200mm depth. Basically you are adding compost to get that 200mm of soil to have a total 10% organic matter. 200 x 0.1 = 20mm. You can go more up to 20% organic content which is double 10m3 : 40mm thick per 100m2 mixed to 200mm depth. Hope thats not too confusing... You only need organic compost, not organic soil.. They are two different things..The compost will breakdown in 6-12months making a permanent change the clay soils structure. If you go over 20% the soil will sink noticably.. This works best with a grass like kikuyu because it happily grows in hard/poor soils without bother. The other grasses will struggle a bit because the clay will compact and there roots will struggle to penetrate through. Santa ana couch might do alright though. If you are going to have a heavily used lawn with kids playing/dogs then i would suggest the second option of adding the sandy loam.. It doesn't compact as much, so any grass will grow better, it's easy to get the water to penerate when irrigating, especially on sloping land.... Grasses are just eaiser in sandy soils.. My rear lawn is clay based and i would definately have added sandy loam rather than just ammending the existing soil if i had my time over... (High wear) Re: Lawn/Turf advice 9Mar 18, 2015 6:50 am Thanks BK! Yeah the lawn will be for my dog, now I get it it's organic compost not soil. I'm definitely going kikuyu. I was wondering can I till the compost in then add sandy loam on top for best of both worlds?? Or is that defeating the whole purpose?? Re: Lawn/Turf advice 10Mar 18, 2015 8:11 am Yep you can do that no probs. Just when you mix the compost through the clay don't mix it deeper than 100mm if poss. The Reason is compost doesn't break down correctly with 200mm of soil on top of it and it could kill the lawn. Don't have to be mm accurate but best you can do. You just don't wont compost deep in the soil as it needs air to do it's thing.. The Soil profile (top soil downwards)would be 100mm sandy loam 100mm compost/clay/gypsum* mix 100mm clay/gypsum* mix Anything will grow in this, you could do your whole block so when you want to plant in garden beds they are ready to go.. Re: Lawn/Turf advice 11Mar 21, 2015 6:34 pm Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ Long day! Got two amazing blokes that came in and helped me excavate my **** clay soil and pop 30m3 of sandy loam on it. Fantastic guys that rock up 7am and finished at 5pm. Now just gotta smash some poly pipes in before my sprinklers Re: Lawn/Turf advice 12Aug 15, 2015 11:36 am BeatrixKiddo Yep you can do that no probs. Just when you mix the compost through the clay don't mix it deeper than 100mm if poss. The Reason is compost doesn't break down correctly with 200mm of soil on top of it and it could kill the lawn. Don't have to be mm accurate but best you can do. You just don't wont compost deep in the soil as it needs air to do it's thing.. The Soil profile (top soil downwards)would be 100mm sandy loam 100mm compost/clay/gypsum* mix 100mm clay/gypsum* mix Anything will grow in this, you could do your whole block so when you want to plant in garden beds they are ready to go.. I am from north west Sydney where there is a lot of heavy clay soil. I keep returning to this brilliant thread by Kyeo and BK with golden advice about preparing heavy clay soil for turf. I have read it several times as my understanding of soil prep has increased and it makes more sense each time. Thanks BK!! OK, so I am now officially hijacking this thread... In my situation, I have non dispersing clay (did the dispersion test), so my 2 sacks of gypsum will likely be on Gumtree some time soon So, I cant have that 3rd 100mm layer of clay/gypsum. So tell me would this work (on a high traffic play lawn (100sqm) and the nature strip 200sqm): 1. excavate so that we are 125mm below paths. dispose of the soil 2. rip 100mm of clay, add Powerfeed and some certified organic compost (or should I leave out the compost, seeing PF is a liquid compost) ? 3. Add a 100mm layer of sandy loam as a top layer 4. lay the turf 5. In warmer months, hit the turf with PF and do mulch mowing What have I missed ? What about a wetting agent (seamungus ??) in the top sandy loam layer ? They using concrete or timber sleepers? Timber or steel uprights? Any drainage behind sleeper? 3 5885 the leaves that are now underground go yellow, the tips that poke through photosynthesise and have chlorophyll, same reason they grow rhubarb in the dark. 5 4878 Versaloc is a mortarless besser block system that still needs a properly engineered footing. If you just do a 400x200 footing it will fail in time. At 17m long you need it… 1 17950 |