Sulphur always need for perennials in Central Oregon?

Asked March 31, 2018, 11:43 AM EDT

Should we as a rule always add sulphur to raise the acidity of the soil in CO for perennials? If so what products would you recommend? I highly amend the soil with compost, peat moss and steer manure but feel many of them could still be doing better. I live between Sunriver and La Pine.

Deschutes County Oregon soil fertility horticulture

1 Response

First, I would ask if you know the pH of your soil at this time? Compost will buffer soil pH to a neutral pH of about 7.0. But, you add peat moss which has a pH of about 4.4, very acidic. If you add peat moss every year you may actually be driving the pH of your garden soil past the range most ornamental plants like, 6.0- 7.5 or slightly higher. If you don't know the pH of your soil now I would suggest getting a soil test before you add anything else to it. Here are some links that may be of interest to you.
https://catalog.extension.oregonstate.edu/ec1585
https://catalog.extension.oregonstate.edu/ec628
https://catalog.extension.oregonstate.edu/em8677