If you started with something that tested 7.0, then added something that tested 5.5 and ended up with something that tested 4.0, I think there's something wrong with the tests.

What you are seeing is common with those unreliable pH meters. Contact your lo9cal office of the Clemson University USDA Cooperative Extension Service about having a good, reliable soil test done.

Here is a link that might be useful: Clemson CES

Did ya use tap water for the test? Try using distilled.

Home pH testing kits are quite reliable - perhaps the only reliable home soil testing kit - but results get thrown off if you use regular tap water.

Regular tap water would increase the pH because it is often buffered up to around 8 to protect your pipes.

This doesn't have anything to do with your testing problem but I don't understand why you would put lime on soil that was already above optimal pH.

I looked up a picture of a Kelway tester. It looks like a conductivity meter that you stick in the soil. Those can be affected by alot of things. If this is the case you might try putting a large soil sample in a container of water and putting the meter in the solution. Also, does it come with standardized ph solutions for calibration?

If you want to do your own soil pH you need to first have a good pH meter and be able to use it properly (I.E. calibration). you will also need a balance capable of measuring accurately down to tenths of a gram. If you have that do the following for what in a lab is refered a "1:1 pH test":

1) measure 40 g of dried, sieved soil into a glass (preferably 100ml capacity)
2) add 40 ml of distilled water to the glass and stir for 30 seconds
3) wait for 3 minutes
4) repeat steps 2 and 3 4 more times
5) wait appx. 5 minutes until a clearer liquid forms above the soil
6) take pH measurement

The 1:1 test is quick, easy and accurate enough in most cases.

Keep in mind that a test is no better than the sample you have taken. For example, if you have a 1000 sq ft garden and went to a corner, took a cupful of soil off the top 2" it wouldn't represent your garden very well. Locate your state land grant college soil lab on the web to find out how to take a proper sample.

Good luck, Michael

I think that michael357 has offered a procedure that is probably about as good as you will get from forums.

michael357's procedure is similar to what we did agricultural college laboratory decades ago. In agricultural college we let the soil stand in the water longer. I've forgotten but I think we have let it stand for a couple of weeks or more but most hobbyist are not that serious.

Michael, question, does that mean adding a total of 160 ml distilled water?
Thanks!

The testing, was it performed over a wide area or just in one particular square. Such testing can be unreliable in that when laboratories do it, you are instructed to take soil samples from many areas. The results are trusted better to represent the actual soil analysis and not from an area where anything might have caused a change.

You added 250 lbs of lime to 3500 square foot area.
Was this a suggestion by a laboratory who is aware of your soil analysis.
In articles describing what amounts should be used they point out such addition of amounts depends on the acidity of the soil and point out too that such amendment be done over a span of time....and not dumped all at once over an area.

You had a reading, if it is reliable, of 7,0...which is well in the range of what reading makes for a good lawn, why the need for liming.

ajpa: I humbly apologize, should have proofed my post better. Total soil is 40g + 40 ml water total, that's where the 1:1 ratio comes from (40 ml of distilled water weighs 40g). In step 4 it should have stated that the stir and rest periods were to be repeated only, not the addition of more water.

You can use larger volumes as long as the 1:1 is maintained. As far as the volume is concerned, I always did them in 100ml beakers which worked well allowing our pH probe to go deep enough into the mixture without touching the sides or bottom.

Albert: maybe that was a saturation extract you were doing, they take much longer than the "quick and dirty" 1:1 and are more accurate. Can't remember exactly but the saturation extract method sits for probably a minimum of 4 hours or possibly overnight after the water is finished being added and stirred in.