London (change)
Today 21°C / 15°C
Tomorrow 22°C / 14°C
7 messages
10/05/2013 at 23:37

I am now getting to a stage with my garden where I have cleared sufficient brambles to start thinking (and I mean, thinking, not actually doing) about selecting plants.  Can anyone suggest a suitable pH meter I can use - lots of those on amazon (replicated on ebay) are cheapo ones, that have got very bad reviews on Amazon, which really puts me off buying them.  I'd rather have a meter that you stick in the ground, rather than a testing kit, as I'm going to be improving the soil as I go along, adding compost and manure, and as I want to grow veggies in the bottom bit, a meter would be useful as I would know if I needed to lime the soil for brassicas.

Anyone got a good one, and should I avoid the cheap Amazon, E-bay and GC ones?

11/05/2013 at 06:33

All l pH meters will be less accurate than soil testing kits, A meter really only works well in contact with water, so drier soil will give a poor reading, and you only measure the pH of the soil immediately in contact with the rod. Taking a small soil sample and adding water followed by the indicator gives a much more accurate reading. 

If you are doing a lot of testing, Instead of buying a kit from a garden centre, you could get hold of something like this, which is a lot more cost effective and less fiddly. 

http://www.amazon.co.uk/Pack-Strips-Universal-Indicator-Papers/dp/B008RFGGTY

and try this method:

1. Dig up some soil,  and put it into a container.

2. Break up lumps till it is reasonably fine. 

3. Add some water (the amount is not critical*, but enough to allow you to dip in the indicator paper - see next step)

4. Dip in a short length of indicator paper and cmpare the colour against the colour chart.

*Oddly enough the ratio of soil to water does not affect the pH level. 

 

 

 

 

11/05/2013 at 06:58

When you say 'add some water' I always use rainwater as our tap water is very 'hard'.

11/05/2013 at 09:18

I don't think it matters dovefromabove. Rainwater is acidic, down to pH 5 and hard water up to 8. I think the important thing is probably to add just enough water to allow other paper to get wetted or, if using a kit, enough to allow you see the colour of the water once the soil has settled. If water pH was critical it would make testing kits useless as the results on the same sample would vary depending on your water supply. PH is a funny thing. If you dilute water with a pH of 5 with distilled water the pH of the mix remains at around 5. dilution does not affect pH. I suspect the soil content is much more dominant than the water content in the test.

11/05/2013 at 13:57

Thanks folks

OH has a stash of litmus paper for measuring the pH of his biodiesel (something to do with having to add acetic acid to the mix after the initial reaction to stop it all turning into soap).  Think I will have to 'borrow' some of it, as he's always sending off for new supplies.  Either that or get my own stash and hide it - he's great at borrowing things on a permanent basis, or borrowing things and giving them back when they're about to give in or are nearly all used up.

11/05/2013 at 18:28

Good thinking! Litmus paper should work well for telling whether the soil is acid or alkaline - it doesn't show you how acid or alkaline, but often you don't need to know that. And its easier to buy it on line than universal indicator paper. 

12/05/2013 at 07:33

That's interesting Gold1locks - thanks 

email image
7 messages