More on pH

I would recommend that you get a professional soil test done at least once for you garden. You will get readings for pH and buffer pH. If your buffer pH is higher than 6.7 you will not be able to change your soil pH. No amount of lime will be able to raise it. You can add lime and you will get a
temporary rise in pH but the number will quickly sink back to the original. I'm not sure why but according to the Cooperative Extension Horticulturalist in Palmer, AK it's a fact. Buffer pH is something your neighborhood chemistry teacher or you test kit cannot tell you.

The buffer pH in the Harvest of Hope Memorial Garden to from 6.7 to 6.9. Since I can't raise the pH, I am very glad the water pH is 5.1 to 5.3. This will still grow everything I need to grow and I don't have to do anything to lower the pH for the potatoes. They love it. The apple trees think it's pretty cool as well.

Be sure to use a lab that is set up to test Alaska soils. There are only a few. You can check the Cooperative Extension Service website for a list. I use Brookside Laboratories in Ohio. They are the cheapest and they do the proper tests for Alaska. You should request test S001AN. The cost is $20 per sample. This will give you everything you need to get things going well.

If you have questions about this you can email me or contact the Cooperative Extension Service.

Changing the pH

You may need to adjust the pH of the soil in your garden. Soils in a Alaska tend to be poor in nutrients and generally acid. Acid soil has a pH lower than 7.0. It is sometimes called "sour" soil. 7.0 is neutral, it's neither high nor low. It's not acid (low) or alkali (high).  Alkali soil is also called sweet soil. Most gardeners try to keep the pH between 6.5 and 7, so just slightly acid. It's impossible to tell the pH of your soil without testing it yourself or having someone else test it. Most green houses and garden centers will test the pH of your soil for you. You might talk with your local high school chemistry teacher to see if they would check your pH for you. You will have to get a sample or multiple samples. If you take multiple samples be sure you label them so you can keep track of the pH in specific locations.

pH, Light, Moisture Tester

You can purchase your own test kit. You will pay from a few dollars to hundreds of dollars. But if you spend more than $20 you are probably spending too much. You should be aware that many test kits have ranges on the pH scale they can accurately test. Testing ranges should be from about 4 to 8.  The tester pictured at the right has a pH test range of 3.5 - 8. I have no idea how accurate it is. At $10 even if it isn't very accurate you won't be on the hook for much money. I have ordered one of these and will let you know the accuracy and ease of use sometime after it arrives. See the tool test for triple tester. It wasn't good.

To keep things in perspective, a pH of 5.0 will still grow great vegetables and the potatoes, blue berries, and raspberries will love it. pH as high as 8 will do the same but you potatoes may look bad.  They will taste just fine but the potato scab makes them ugly. Making soils more acid is generally more difficult than making them more alkali. Instead of rewriting what other people have said about this I will provide this link for more acid and this one for more alkali. There are many other websites that will point you in the right direction just key in changing the pH of my soil on any search engine and you will get more articles that you could read in a year. If you are going to err make it on the side of acid soil.

There are certain plants that like quite acid soil (potatoes) and some that like quite alkali soil (honeysuckle). Check the seed packets, ask the representative in the garden center or greenhouse, or look it up online.