Pine Bark Mulch 1Liter by Plant Cullture PHPine Bark Mulch 1Liter by Plant Cullture PH Keep the soil moist and moderates soil temperature Reduces weeds by preventing seeds from sprout Gradually decomposes and adds humus to soil giving it a loose and crumbly texture It comes to shreded or nuggets form. Any organic mulch benefits soil and plants by retaining moisture, protecting plants from extreme cold or heat, and preventing the spread of soil borne diseases. This is true of pine bark mulch as