Topsoil

[reallyok]

I am about to build on Samui, the soil is "siht" and i want a decent garden and lawn. Is it possible to buy decent topsoil either here or the mainland.

[WatersEdge]

The tonnage required to overlay a yard with topsoil is huge,

so therefore the cost with it.

Planting something that requires a lot of care to get a little growth isn't worthwhile,

but if there was a plant that would grow extremely fast

to build mulch bulk in the soil,

then kill it when you are ready to plant the yard,

you would have made your own topsoil on site.

I suggest that you plant Napier Grass,

since it expands clumps quickly from pieces broken off another clump

and will respond well to just water and fertilizer on sand

In a month of good conditions, it will multiply 10X,

and then each of those sprigs

broken out and transplanted

will form another clump in the month to follow

It doesn't take very many months of 10X multiplication,

until you have solid coverage.

Left to grow a few more months,

the roots will steadily work downward

forming a solid mat of root mass.

If you let the same clump reach downward for a few months,

you can then just chop the tops off with a bit of root below,

and the remaining deep roots will immediately sprout afresh.

I don't know how deep they will eventually reach,

as my experiment with it is only a bit over a year.

but I continually am amazed at what it does.

That's below ground.

Above ground it is a good forage / mulch if cut before 60 cm tall.

Higher than 60 cm it turns coarse and shoots up to over 2 meters

looking something like young bamboo.

When it comes time to plant the desired yard plants, Roundup (Glyphosate) will kill it.

It should also be mentioned that it will lie dormant under the surface in dry times,

popping back up from the root as soon as water arrives.

It does require fertilizer for fast performance,

as any fast growing plant with feed value.

It will not do well in flooded areas, but it does like water in the soil.

I'm inland, so I can't say how it does on salt soil.

I also have Vetiver grass on the same farm,

but it does not spread nor grow as fast as Napier

and is much more difficult to break apart and transplant.

Given the choice,

Napier outperforms Vetiver in every way.

My original intent is animal forage,

but now I see much more.

[drtreelove]

I don't know what's available on Samui, but look around for materials supply yards that have rock and sand for construction projects. Go in and look for piles of soil and ask. Here in Chiangmai we get river dredge that is a silt loam and faily decent if you mix in enough organic matter. It goes for 800 to 1200 baht per 5 cu meter six-wheeler, depending on supply and demand at the time.

Watersedge is right on the alternative of growing a "green manure" cover crop and then tilling it in will improve what you've got, but that takes at least a couple of years to build some decent soil structure and fertility. I haven't used the materials he's talking about, but standard green manure crops are legumes like black beans or jack beans.

If you find some topsoil, or try to work with what you've got you will need some organic matter to incorporate for building soil fertility. If you can find real compost you will be lucky. Isn't Samui a big coconut producer? You may find bulk ground coconut husks, rice hulls or other organic matter to work in.

There are some members on this forum from Samui area, hopefully they will see this and give you some definite leads on sources. You might post your question on the Southern Thailand forum too, as this is not just a farming issue.

[Beardog]

In Thailand it is difficult to get (Din Dam) Black topsoil. Usually it is mixed with soil coconut & Key Quai.. What we did was get some decent subsoil- Not super duper- but had the small excavator dig down & mix a lot of bull shit into the soil. The lawn looks fantastic. We used a form of nippon for the finer lawn & Malaysian for the shadier areas as nippon does not do well in shade. The fruit trees & flowering trees & Vegetables are off the hook. I think the key is in Either the animal excrement. Cow Chicken Pig Bat or whatever( the cow tends to not be as stinky ) & works wonders. we use mainly organic fertilizers except we do have to spray for aphids on certain(non Fruit) trees. If you use a soil with a lot of sand- the sand will always rise to the surface. Make sure you weed very well before you load the soil. It is a pain in the ass as the weeds will always be there if you don't. we rarely have crabgrass come through & our neighbor that laid his turf over sandy rocky surface has a weed garden. He wasn't as diligent on the weed removal. That & the cat we had dig the hard subsoil in & mixed the topsoil with dung was the ticket. To get the grade a Din Dam(similar to peat moss would be very very expensive. So I would look around for a good topsoil(usually not black, unless someone has an undefiled swamp they are dredging & add in lots of manure. Wait a week for the manure to blend in & either seed or sod. Ours was sod.If you get sod you need good soil as they are not to generous with giving you soil with the sod as in western countries. Water copious amounts of water for 2 to 3 weeks & you will have a winner on whatever grass your growing.

Edit: Do not be afraid to send the soil back if it is not up to snuff. The first load from one company was a light load for top dollar & was 50% sand. We refused the load & told them that if they can come up with real soil give us a ring.

Better them be mad at us than us hating them later & paying for a 13 cubic meter load & getting a 10 cubic meter truck.

Edited December 13, 2009 by Beardog

[wescue]

Rice hulls made into charcoal. ie not burnt to ash but pyrolyzed. Spread over the soil. Try to make it a few inches deep but 1/2 an inch is good.

But first charge the char with urea or some fertiliser other wise the char will draw the available nutrients into itself.

You can buy this product from rice farmers.

This will improve soil. Every gram of the char has around 250 square metres of surface area and it absorbs nutrient from the rain and metres it out to the plant roots as required.

I use this in an orchard and it is...just great

[jandtaa]

^ 

I'm a big proponent of CRH (carbonised rice hull) but to use it effectively I believe it must be tilled into the sub-soil . There is no need to charge it with urea etc... if it is simply going to be used as a mulch (the nutrients will simply leach out with rain and run off the soil in the usual manner, by incorporating it there will be no problems with it absorbing nutrients from the soil below and making them inaccessable to the plants) and plain rice hull or rice straw may well be a better choice. If you're going to incorporate it into the soil a better option for charging it would be EM. CRH has many benefits but one of the major ones as you point out is the large surface area of its micropores, which make it an ideal substrate for the growth of soil micro-organisms, which will break down nutrients in the soil and make them available to the plants . I would recommend creating a soil conditioner from it such as ; 4 parts CRH charged with EM : 4 parts cattle manure : 1 part rice bran : 1 part compost. I'll post a more complete recipe and method later if anyone is interested.

cheers for now J  

[reallyok]

^

I'm a big proponent of CRH (carbonised rice hull) but to use it effectively I believe it must be tilled into the sub-soil . There is no need to charge it with urea etc... if it is simply going to be used as a mulch (the nutrients will simply leach out with rain and run off the soil in the usual manner, by incorporating it there will be no problems with it absorbing nutrients from the soil below and making them inaccessable to the plants) and plain rice hull or rice straw may well be a better choice. If you're going to incorporate it into the soil a better option for charging it would be EM. CRH has many benefits but one of the major ones as you point out is the large surface area of its micropores, which make it an ideal substrate for the growth of soil micro-organisms, which will break down nutrients in the soil and make them available to the plants . I would recommend creating a soil conditioner from it such as ; 4 parts CRH charged with EM : 4 parts cattle manure : 1 part rice bran : 1 part compost. I'll post a more complete recipe and method later if anyone is interested.

cheers for now J

Thanks to you all for the info. Guess i will just have to think a little.