From

Location

Message

Date Posted

Goffstown,nh

I am curious, did you add 15Lbs. of ammonium sulfate per 1000 sf. of garden area to lower your PH?

4/14/2026 6:29:40 AM

Grittyville, WA

Potassium and magnesium are about the same in ppm"s, but in % of CEC magnesium is 3x higher than potassium... Is one of these numbers wrong? I swear I never understand these tests.

4/14/2026 8:57:53 AM

Missouri

Jim, Yes and no, I added 4.4 lbs of ammonium sulfate which can lower pH, but the elemental sulfur I added will be much more effective at that and better at lowering pH over time. The ammonium sulfate will provide faster availability of sulfur for plant growth, short term pH lowering, and additionally some nitrogen. This amount added the total fast acting sulfer recommended but I still needed more nitrogen which is why I also added urea (fast acting) and feather meal (slow release) to have nitrogen available over the growing season.

4/14/2026 9:23:25 AM

Missouri

Brandon, agree with how confusing this can be, but here is a pretty good explanation from Western Laboratories on the cation exchange capacity...
https://files.constantcontact.com/42dc39f7701/65ff25fc-6c09-4c1d-bee4-a0aa8173c706.pdf?rdr=true

4/14/2026 1:32:17 PM