Everyone has probably heard of soil pH at some point in their gardening experience, but what is "pH'?...What does it mean? What difference does it make to a gardener? These and other questions are going to be examined in this posting. I have been reading books and on the internet to fix in my mind and to re-enforce past knowledge on this subject. I find the soil the most important, that is to say, essential component in the gardening equasion and I like to sort of refresh myself on this subject each year. This year I wanted to concentrate on pH. What Is Soil pH pH stands for "potential hydrogen". It is the measured indication of alkalinity or acidity of (in this case) soil. The pH range extends from 1(very acidic) to 14 (very alkaline), neutral being 7. Most all soils fall within a pH range of 5 and 8, with the ideal being 6.5-7. Soils that fall outside this range will need amending in order to support many plants and crops. Why Is pH Important It matters because plants take their nutrients up in a soluble, molecular form. When we measure our soil's pH we are in fact measuring the moisture that is in the soil. The moisture's pH is determined by its surroundings--the constituents in the soil; and the pH of this moisture (or water, if you prefer) determines how easily the nutrients get taken up into the plant via the hair roots. Another way to explain it is that if soil is holding certain minerals in it, but the pH is such that the micro-organisms responsible for breaking down organic matter are prevented or inhibited from doing their work--the breakdown and uptake process will not happen or will be impeded. Various minerals are most soluble in an acidic soil and others, in a more alkaline one; thus, if you want your plants to get the most out of the soil (to perform optimally), then you need to try and provide the conditions where they can most easily get what they need. Measuring pH Well then, before getting started with any tweaking that you may wish to do, you first need to make a measurement. How do we do this? Basically there are three methods of testing and one is by using a probe. The other is by purchasing one-use "kits". The third is by "third party analysys". The probe has a probe with a meter on the other end which will indicate the pH. The cost can be a little expensive, but the upside is that you can use it over and over again. The testing kits could have litmus paper or reagents that you put in the testing container along with a soil sample. The fact that you must do it yourself could be seen as a negative, I suppose and the fact that you can only use it once per unit. On the positive side is the cost--they are usually fairly inexpensive. You could make an arrangement to send a soil sample(s) off to a lab; however, this is not economical-- just for a pH measurement alone. If you do do this, then you could have your soil analyzed to find out what the mineral composition is as well. This way you would get more for your money. It is going to be on the expensive side though, as well as slow. ***A tip here is that you ought to take samples to be tested from several different locations in your plot or garden, rather than just one. When I have tested my soil I have also gone so far as to test my soil at different depths. Once the results are in, you can see if your soil falls within the "best/ideal range" or not...or if it is too alkaline or acidic for what you wish to grow. You can make adjustments in order to bring your soil to within the ideal range, or to purposely make your soil acidic or alkaline...depending upon what your goal is for a particular plot or area. Lowering pH in an Alkaline Soil This will be somewhat more difficult than raising the pH in acidic soils. It may leave you frustrated because any change will be small and significant change will occur after persistent amendments over time. What you could do: --You can use things like sulphur additives. --Add commercially bought soil especially for Rhododendrons or Azaleas. This already had a ideal pH. --Add/mulch with materials that you may have handy, like pine needles, manure, grass clippings, leaves or rotted wood chips or sawdust. Additionally, it would be easier for you to get the pH that you want if you make a raised bed or use a container to grow veg, fruit trees/bushes in or special flowering plants. it is easier because you do not have to adjust or amend existing soil--you buy your ideal soil pH in a bag, commercially. Perhaps it is not fun, but it is effective and as I said, easy. Now, you can mulch your patch and that will give the upper layer an adjusted pH to some extent; however digging the mulch in gets it to a lower level in the soil. That is to say, nearer the roots. The trade-off is that it may not last as long. Raising pH in Acidic Soil This is not so difficult as in the situation discussed above. What you could do: --Obviously the first thing coming to mind is the addition of lime in some form, eg some lime powder or beads, calcified seaweed or burnt wood ashes. ***It is worth knowing that if you add manure and some lime compound at the same time, quite a bit of the nitrogen could be released into the air. This goes for fertilizers that consist of nitrogen in the basis as well. --Add and dig in compost in order to bring the pH up. --Look into improving soil drainage and cover the soil during non-growing months. You know, this pH thing--We can see the obvious benefits of having the pH at a good level for your needs, but the truth is that it isn't always easy to achieve and it may take time. In these times, it seems that many folks have a sort of "hurry-up, I don't wanna wait" mentality and so becoming discouraged is a possibility. I would suggest that if you want to pay attention to your soil's pH, then do it NOT in a fanatical way, but rather just do your best and work at it a little each year until you reach your goal. Gardening is supposed to be fun, not an obligation with time limits. Good luck.
I try to keep my PH levels between 6.5 and 7.5 as I prefer a neutral soil. My plants seem to appreciate what I do for them so we're all happy bunnies. :-D
Thanks so much, FRANK--it is especially nice to get a compliment from you. It sounds like you have everything under control there, EILEEN. I knew that you knew lots about this subject. You are so welcome, JERRY--I am pleased that you liked this posting enough to print-out and put aside. That is a very nice compliment. Thanks.
great reading sjoerd, i've been meaning to test mine since i moved in here and haven't got round to it yet
pH is a logrhythmic scale, so every one change from 7 is ten times the next. I have a pH of about 5.5 here in the northwest USA, and it would take ten times the amount of lime to change it from 5.5 to 6, than from 6 to 6.5 and one hundred times as much to change it to seven So I personally don't fight it for the yard. I enjoy wonderful rhododendrons, blue hydrangeas, huckleberries, and a lot of moss in my lawn. I have all my herbs in a raised bed, so can control the pH there much easier.
Very informative post, Sjoerd. I'm where Karrma is. Our soil is naturally acid and we also grow acidic-loving plants. We've got lime-lovers too, and mix the lime around the plants and supplement with shell sand that releases the lime slowly. Since they look healthy I guess they like things the way they are.
Thanks KK-- Glad that you liked the posting. Thanks for your contribution, KARRMA. Thank you for your nice words,DROOPY.
Hi Sjoerd, This was a great post! Very informative... I think I will copy it! I have explained this concept to my customers a lot. You make it easy to understand. Thanks!
Thanks so much for your posting, Kay--That was very nice of you. I am glad that you liked it. I am also glad that it was clear to you. You know, I can read over posts many times, but I never really know if people other than myself will clearly understand what I am trying to 'put down on paper', as it were.
I am just ready to get back to my sandy loam.It will be so nice to get down in the dirt Sjored it was good to see you still ask questions.Its good to see you buddy.
