Soil testing kit - don't understand the results!

[Curlykale]

Please don't laugh if I'm being thick, but I'm having difficulty getting my head round the B&Q soil testing kit colour chart.

It says on the back of the kit ..................."instructions on how to test your soil pH and nutrient levels and how to use the colour chart below can be found inside this pack together with pH and nutrient level preferences for a range of flowers and vegetables". ............... Inside the pack it merely tells you how to mix the soil and liquid and ..........."compare the colour of the resultant solution with the colour chart to determine the pH of your soil sample"................

I took some samples from different parts of the lottie. I was hoping for some pretty green/yellow results confirming the soil is neutral or slightly acidic (at least I think that's what I want for most of the veg isn't it?) but all I got was, well - diluted soil coloured liquid.

I thought I must have a dud kit so bought another - but just got the same results.

The colour chart has 4 columns - one for the pH and others for the levels of Nitrogen, Phosphorous and Potash. The Potash boxes on the chart were all various shades of brown - does that mean that my kit has measured the Potash in the soil and I should match the sample with the nearest shade of brown on the chart? (which would be between medium and low). Do I then go along the chart to the same box in the pH column to find the pH? If I did that it would be between 6 and 7 - but if that is the case why isn't the solution green/yellow?

I thought the idea of the kit is to find out the pH - I'm very confused!

Is there a better kit/way of testing the pH?

[BFG]

I'm not sure what the problem is. Where are you getting green and yellow from?

You should just compare the test liquids colours to the colour charts. 6-7 sounds reasonable for PH.

[Jeanied]

The problem with modern soil testing kits is that you do not filter off the soil - so you are trying to measure mud coloured liquid against a coloured strip.
A couple of ideas - firstly only test a dry soil sample which is not in lumps. Secondly let it settle a good while before trying to read the colour levels. Some soils take quite a while to separate from the liquid.

[oldie]

The instructions for the pH kit I have used says:- take a soil sample and let it dry naturally, put said sample in tube add a scoop of the enclosed powder(scoop provided and powder is barium sulphate), then top up to a measured level with the liquid provided. Leave for 10 minutes - if the soil has not settled to the bottom add some more powder and leave for a further 10 minutes. The soil should have settled to the bottom of the tube leaving a coloured liquid on the top. Compare that colour with the chart and you have your result. I have never bothered with nitrogen, phoshorus and potash levels so I don't know if your instructions need you to test different samples for each or whether one test shows all, which I would doubt. Hope this helps!

[Glutton4...]

Much easier to get one of the metal rod sensors; push it into the ground, and the needle moves across to the correct PH on the dial - Seemples! Had mine for years, so couldn't begin to guess where I got it, or what it cost, wasn't much though.

[Bigmallly]

Much easier to get one of the metal rod sensors; push it into the ground, and the needle moves across to the correct PH on the dial - Seemples! Had mine for years, so couldn't begin to guess where I got it, or what it cost, wasn't much though.

£3.98 @ Wilkos.........

[oldie]

Easier but how accurate? I tried one which said my soil was acidic but other tests showed a pH of 8

[Curlykale]

I'm not sure what the problem is. Where are you getting green and yellow from?

You should just compare the test liquids colours to the colour charts. 6-7 sounds reasonable for PH.

Green and yellow were the colours on the pH column on the chart - the only column that had brown boxes was the Potash column.

I did leave it for a long time and kept going back to check but the colour didn't change.

It didn't say to dry the soil though - I'll try doing that next time.

I've been looking for one of those sensors but haven't found them in any of my local GC's, and our Wilkos don't have them.

Thanks for your replies everyone.

[Bigmallly]

Having never used one of these testers before, is it the soloution that changes colour or do you get litmus paper & do the old school dip stick trick.

[Curlykale]

Bigmally, the solution changes colour (or is supposed to!). You put a bit of soil in the bottom of the test tube and top it up with the liquid they supply. You then shake it and leave it for 10 minutes for the soil to settle on the bottom before checking the colour of the liquid. I left mine for an hour and it still made no difference!

Perhaps I should get some litmus paper if that would be more accurate- would you just mix the soil with water?

[Bigmallly]

I'm only guessing but I would think yes. It would show the acidity of the solution.

[oldie]

If you just use water you would need to do a test on that as well as it could also influence the result, that is why the kit contains a liquid to add to the soil sample.

[zazen999]

Curly - were there different liquids to add; and have you done a tester with some lemon juice to see if it turned colour then?

[Helgalush]

Hi, I used a Homebase one which sounds a little simpler to use, although essentially I guess it is the same sort of kit. But it only tested PH, it didnt do the nutrient content as well, and I think that the powdery stuff was already in the test tube.

[Curlykale]

Curly - were there different liquids to add; and have you done a tester with some lemon juice to see if it turned colour then?

Zazan - no, there was just one bottle of liquid.

Great idea to test lemon juice - will have a go with that - thanks!