Posted by Sparki | Posted in Raised Garden Beds | Posted on 26-02-2012
Lowering the soil pH in your Houston garden to the optimum range for the plants you want to grow provides an ideal environment for your plants to absorb the balanced nutrition that organic matter rich soils provide.
Sphagnum Peat Moss
I have found the fastest way to lower your soil pH organically is to add Sphagnum Peat Moss. When I incorporated Peat Moss into the soil with my potted Blueberries, the drop in soil pH was immediate.
If you have plants that like very acid soil, like Blueberries and Azaleas, I recommend that you plant them in a soil mix that has lots of sphagnum peat moss in it to begin with.
As a matter of fact, Azaleas will thrive in nothing but Sphagnum Peat Moss. If your landscape soil is not naturally acidic enough, I recommend growing the smaller varieties of Azaleas in containers rather than in landscape beds so you can control the soil in which their roots live. In landscape beds, Azalea root systems will eventually find less acidic pockets of soil.
To lower soil pH organically, you can use elemental sulfur (flowers of sulfur). Elemental sulfur is converted to sulfuric acid biologically by soil bacteria. But in order for Elemental sulfur to affect soil pH levels, follow these recommendations:
- Keep the soil moist. Bacteria need a consistently moist environment to thrive.
- The soil must be aerated. Bacteria need oxygen.
- The soil must be warm to promote rapid bacterial growth and activity. Thus, it will do little good to try to lower soil pH with Elemental sulfur during the winter months.
- Apply Elemental sulfur to the soil surface and use a hand held cultivator to carefully scratch it into the soil. It must make good contact with the soil where microbial bacteria live.
Then, you must be patient and give the bacteria in your garden soil time to do their thing. The finer the particles of Elemental sulfur you use, the faster they will break down by bacterial activity and the faster they will affect your soil’s pH.
In the meantime, if you’re using municipal water to water your garden, you will be working against them and yourself. Municipal water raises soil pH. You will find yourself fighting an uphill battle against rising soil pH levels until you switch to watering your garden exclusively with rainwater.
To lower soil pH chemically, use products containing Aluminum Sulfate. Aluminum sulfate will change the soil pH instantly because the aluminum produces soil acidity as soon as it dissolves in the soil. The presence of chemicals, however, will adversely affect soil microbial populations. That’s the trade off.