That is a very high pH. I would ask the supplier of the soil if they have tested it, and what their results are. Home test kits are notoriously inaccurate.

There is one way to get pH that high: if manure was added that was treated with lime. Hydrated lime (not powdered limestone) is often used in horse barns, etc. to control odors and has an extremely high pH. If alkaline manure was mixed into the soil, it can have a pH of 9 or even higher.

If your pH is actually that high, sulfur will take weeks or months to work.

What is the pH reading of your native soil?

How much of this new soil did you bring in?

" How long does the soil need to stabilize before I should try another test to see what the new pH level is? "
A couple of months ...

"Since the Sulfur breaks down I guess I need a resupply plan."
Yes ... applying sulphur is needed every couple of years.

Your best plan is to get LARGE quantities of organic matter into the soil and on it as mulch.

Look up "lasagna gardening" ... you just apply layers of organic material to the area and plant in it. Do this only on the areas you actually grow things in, and have the rest of the area be paths. Clay is especially easy to turn into hard compacted dirt, so minimize walking on it.

Also, plant okra ... it's tough, handles high pH and clay, and has a HUGE root system. When the plant dies, cut it off at ground level and leave the roots. They rot, and leave organic matter 2-6 feet in the soil, with a network of tiny channels where the roots were. You can eat the okra and compost the leaves for the next year.

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This shows my garden in Arizona, the first year. We started with alkaline desert dirt that was so hard I used a mattock to dig holes for planting. I did NOT till, I just layered wood chips and compost over the top as a mulch. Now, with no tilling, I can dig anywhere in that bed with a hand trowel.

https://www.flickr.com/photos/38617480@N07/3614575147/in/set-72157619486607319

Here is a link that might be useful: okra

Regarding sources of organic material for improving your soil, I imagine that peat is pretty expensive in Cyprus, even without getting into the ecological arguments against it, in a European context at least.

I seem to remember great piles of Carob waste beside roads there. Can you get hold of any of that? Other possibilities would be olive and grape waste. I don't remember seeing them in Cyprus but I have on some of the Greek Islands.

Thank you, toxcrusadr, our land was farmland for about 100 years before (over a 5 year span) the crops just refused to grow. In 1976 the farm failed and part of the land was bought by my (then) future Mother-in-law as an eventual wedding present for her only daughter. They fertilize with manure here and the cheaper the better so your scenario is entirely possible. My âÂÂgoodâ soil (new, bought, whatever) is, in typical Cypriot business fashion identical to my original soil in the back garden (I sent a sample for testing from front and rear gardens and received the results yesterday afternoon) the only difference being the expensive (read wasted) Peat Moss I stirred into the front garden. I am convinced they charged us 600 Euros to move the dirt they dug out for the house from the backyard to the front. Since 1976 the land has lain fallow and been used as parking or festival grounds or whatever the moment called for.

Yea! I like Okra! Thank you lazygardens, I have already stripped the neighborhood clear of green weeds that have not yet produced seeds and buried them where I hope to eventually grow something other than rocks. Right now only my Rock Garden is expanding. Even the cactus plants I have scrounged from the roadsides near our house are struggling to survive in this soil. As for the compacting... without any tree roots, cables or pipes involved I have broken 4 tines and 2 handles (one fiberglass, 1 hickory) off of 2 garden forks and the spike off of a grubbing hoe (Texas & Louisiana name- according to Google it's a long handled mattock) just trying to get the surface broken enough to bury the weeds. Would sprinkling the weeds/plant matter with sulfur before I bury them be of any benefit, do you think? A few times over the next 2 weeks I'll be going up to the mountains where there are pine and cedar forests, I was planning to bring back a few bags of fallen needles and etc. Maybe even catch a few worms (I've not seen one worm in 2 years of fighting with this soil) if I can get away with it. I've read these needles are bad for acidic soils so would they help mine?

Thank you, Floral_UK, yes, I blew most of my garden budget on that mess last year to no real effect. I'll be on the lookout for carob processing centers as I travel over the next couple of weeks. Have a good summer, all of you.

Keep in mind that earthworms feed on organic matter so if a soil lacks OM there will be very few, if any, earthworms living there. Earthworms also tend to stay away from alkaline soils, preferring slightly acidic (6.0 to 6.8) soils with ample amounts of organic matter.
Although your soil is calcareous, limestone, I would doubt a soil pH of 9.0, especially if you can handle that soil with bare hands without getting burns.

Hello, kimmsr,
I thought it was high as well so explained the results to a company here who "CLAIMS" to test the soil in their lab, but, again getting the exact same results from them as I got seems a bit far fetched; however there's no doubt it's alkaline. My kids have gotten little spots on their hands, elbows, knees any bare skin after they've played in the garden and since the weeds are gone, the soils been watered and turned there's not much but the soil that I can see as the culprit. Their skin is much more sensitive than mine. When I added sulfur and turned to mix and watered the soil foamed from the reaction.

sorry thought I added "didn't foam a lot, but enough to notice"

If it foams, then the pH is high and can not be changed. You will have to add a lot of organic matter before you can grow anything. Two feet of wood chips probably, and you will have to select only tolerant vegetables. If you find only or mostly dead wood to amend, try hugelkultur.

PS. I think you need to decide what you want to grow. If it is vegetables, make raised beds with the hugel technique or some type of organic matter. Plants will get nutrients from the top of the soil. Of course, raised beds in a semiarid area are not a grew thing. Bu either way, lots of organic matter (ground on top, large pieces buried) where you want to grow trees or vegetables, and nothing where you don't want to grow.

You don't have to dig it in ... just layer it on top, keep it damp, and let it decompose there.

Carob waste as a mulch could help.
Olive pomace would be oily and hard to decompose.

It's better to mulch a small area thoroughly than spread a skimpy layer over a large area: Start with one area for a vegetable bed and focus on it, then move on to the next area when the first is doing well.

Ont tactic is to have your compost heap where you want to start the next vegetable bed ... under the compost heap will be greatly improved by the time you finish it and use it.

Keep in mind that the Cypriots have been growing both food and flowers in that soil for eons, maybe talking with some of them will shed more light on how to work with that soil then some here can.

I don't think they have. There are parts of the island that are barren.

Elemental sulfur should not react with soil regardless of its pH. Sulfur is not acidic in elemental form, it requires soil bacteria to metabolize it over time, creating sulfuric acid which reacts with bases, lowering the pH. Any foam you observed could not have been from a direct reaction with the sulfur.

You can also use aluminum sulfate, or iron sulfate, to lower pH more rapidly. They are usually applied as a diluted water solution.

I agree that lots of organic matter will help to bring down the pH as well, but it will take time.

I don't really understand how a soil exposed to the elements can have a pH that high for a very long time. Typically limestone based soils top out at about 8.3, the carbonate buffer pH. But I know next to nothing about Cyprus soils. :-]