Garden Soil Treatment! - Page 2

PureHarvest · April 24, 2018

Don, I know you would have to take 8 tests, but without doing them you are really just making wild guesses as to what your soil needs.
Keep in mind that bacteria break down elemental sulfur and this is a slow process. You might not see a big change even if you were to sample a year after adding the sulfur.
People growing blueberries are always fighting this need of a low pH.
This info might be of help. It is for lowering pH for blueberries, but the science still applies:

With the popularity of blueberries
many people are interested in quickly adjusting their soil pH. Acidifying soil is not an exact
science; this handout is just a guide. The cheapest way to lower the soil pH is to add
elemental sulfur to the soil. Soil bacteria change the sulfur to sulfuric acid, lowering the soil
pH.
If the soil pH is greater than 5.5, apply elemental sulfur (S) to decrease the soil pH to 4.5
(see Table 1). Spring application and incorporation work best. Soil bacteria convert the
sulfur to sulfuric acid lowering the soil pH. It is important to note that this is a biological
process (slow) and not a chemical reaction (rapid). The bacteria are active, when the soil is
moist and warm. The soil temperature needs to be above 55F. The bacteria are not active in
the winter so fall applications of sulfur have little effect on the soil pH next spring. In addition,
the soil must not be saturated, or flooded (anaerobic) or the sulfur is converted to hydrogen
sulfide (rotten egg smell) by anaerobic bacteria. Hydrogen sulfide kills plant roots. Irrigate to
maintain soil moisture but do not over irrigate the soil. This causes flooding and anaerobic
conditions. Most Michigan irrigation water is high in alkalinity (dissolved lime) and will
gradually raise the soil pH.
The amount of sulfur required is dependent on soil texture. Clay and organic matter act
as a buffer, absorbing and releasing mineral ions. Relatively little sulfur is needed on sands,
whereas soils high in clay or organic matter require much more. It is important to apply and
incorporate sulfur at least a year before planting. This allows the sulfur time to react and
lower the soil pH before planting. Do not assume that the change can be completed in a
short time. If large changes in pH are needed, than the change will that longer than a small
change.

Sulfur cannot be easily incorporated to the soil after plants are present. Surface-applied
sulfur provides the same pH reduction as incorporated material, but takes longer. Check soil
pH again before planting and apply additional sulfur if needed. Do not apply more than 400
lb. sulfur per acre at a time to established plantings. When large amounts are needed,
spread the application out over several years. Cultivation to aerate the soil and irrigation to
maintain soil moisture can speed the process.

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April 24, 2018	#16
PureHarvest Tomatovillian™ Join Date: Mar 2014 Location: Mid-Atlantic right on the line of Zone 7a and 7b Posts: 1,369	Don, I know you would have to take 8 tests, but without doing them you are really just making wild guesses as to what your soil needs. Keep in mind that bacteria break down elemental sulfur and this is a slow process. You might not see a big change even if you were to sample a year after adding the sulfur. People growing blueberries are always fighting this need of a low pH. This info might be of help. It is for lowering pH for blueberries, but the science still applies: With the popularity of blueberries many people are interested in quickly adjusting their soil pH. Acidifying soil is not an exact science; this handout is just a guide. The cheapest way to lower the soil pH is to add elemental sulfur to the soil. Soil bacteria change the sulfur to sulfuric acid, lowering the soil pH. If the soil pH is greater than 5.5, apply elemental sulfur (S) to decrease the soil pH to 4.5 (see Table 1). Spring application and incorporation work best. Soil bacteria convert the sulfur to sulfuric acid lowering the soil pH. It is important to note that this is a biological process (slow) and not a chemical reaction (rapid). The bacteria are active, when the soil is moist and warm. The soil temperature needs to be above 55F. The bacteria are not active in the winter so fall applications of sulfur have little effect on the soil pH next spring. In addition, the soil must not be saturated, or flooded (anaerobic) or the sulfur is converted to hydrogen sulfide (rotten egg smell) by anaerobic bacteria. Hydrogen sulfide kills plant roots. Irrigate to maintain soil moisture but do not over irrigate the soil. This causes flooding and anaerobic conditions. Most Michigan irrigation water is high in alkalinity (dissolved lime) and will gradually raise the soil pH. The amount of sulfur required is dependent on soil texture. Clay and organic matter act as a buffer, absorbing and releasing mineral ions. Relatively little sulfur is needed on sands, whereas soils high in clay or organic matter require much more. It is important to apply and incorporate sulfur at least a year before planting. This allows the sulfur time to react and lower the soil pH before planting. Do not assume that the change can be completed in a short time. If large changes in pH are needed, than the change will that longer than a small change. Sulfur cannot be easily incorporated to the soil after plants are present. Surface-applied sulfur provides the same pH reduction as incorporated material, but takes longer. Check soil pH again before planting and apply additional sulfur if needed. Do not apply more than 400 lb. sulfur per acre at a time to established plantings. When large amounts are needed, spread the application out over several years. Cultivation to aerate the soil and irrigation to maintain soil moisture can speed the process.