GardenBanter.co.uk - View Single Post

Moe DeLoughan · 14-01-2014, 02:03 PM posted to alt.home.lawn.garden

On 1/9/2014 2:12 PM, wrote:

Common use fertilizer used to come pretty generic, like 8-8-8,
10-10-10, 13-13-13, with little-to-no micro-nutrients. Last spring
I started seeing something different, like 10-10-10 with "up to 8%
sulfur" and "up-to-12% chlorine". That's not MICRO-nutrients!

No, they're secondary nutrients.

I contacted the factory and asked why, and got weird answers. "Soil
needs sulfur and they are eliminating it from industrial
smokestacks",

No, no, no. It comes from the basic source of potassium for that
fertilizer. Potassium is the third primary element (NPK). The most
common sources of K for chemical fertilizers are Potassium Chloride
(yes, chlorine) and Potassium Sulfate (yes, sulfur). The amount of
sulfur present in the fertilizer isn't enough to significantly change
the pH of the soil unless you were to drastically over-apply the
fertilizer. Don't worry about it. As for the chlorine, it's another
essential element for plant development, but like all elements, some
plants are more sensitive to it than others. Soils in coastal areas
tend to have higher levels of chlorine, whereas soils far from the
coast tend to have fairly low levels of chlorine.

and "Don't use chlorine if you plant tobacco" (what
about veggies?)

In the case of tobacco, an oversupply of chlorine affects the ability
of the dried leaf to burn cleanly. In most cases of home gardening,
use of potassium chloride-containing fertilizers will be just fine. In
fact, in areas where the natural soil level of chloride is low (such
as the US Midwest) applying a chloride-containing fertilizer can be
beneficial. Some of the benefits are increased crop yields, improved
quality, and increased disease resistance in plants. But if you're
concerned about it, look for a fertilizer whose potassium content come
from potassium sulfate.

Also, chloride is water soluble and will leach out of soils over time.
It's not usually an accumulator.