Apply Mulch to Further Improve Soil Conditions
Mulch is a covering placed around plants or covering the ground in lieu of plants, to prevent the growth of weeds. If placed around plants, mulch provides additional benefits, including the diminution of erosion and water loss, and the regulation of soil temperature. Minerals, released as the mulch degrades into nutrients, soak down into the soil and fertilize existing plants. Humic acid, a by-product of the decay, clumps together small particles of clay to make a lighter, fluffier soil. In addition, upon decomposition (for organic mulches), mulches serve as soil amendments. The type of mulch you select can also affect soil pH.
Mulch is Environmentally-Friendly – It Can Help Conserve Water
Mulch provides a barrier between the top of the soil and elements, which reduces the loss of water from evaporation. The reduction of water due to mulch will help conserve water use in your garden.
Mulch is usually applied towards the beginning of the growing season, and may be reapplied as necessary. It serves initially to warm the soil by helping it retain heat. This allows early seeding and transplanting of certain crops, and encourages faster growth. As the season progresses, the mulch stabilizes temperature and moisture, and prevents sunlight from germinating weed seed. In home gardens, organic mulch is usually spread by hand around emerged plants. Organic mulches are usually piled quite high, six inches or more, and settle over the season.
Tips:
- Woody mulch, like shredded bark, consumes nitrogen as it decays. Apply extra nitrogen to ensure a proper supply for plant growth.
- Do not apply fine-textured mulches, like grass clippings, in thick layers that can mat down and smother the soil.
- Mulch helps to keep the soil moist. Use it in well-drained areas so that the soil does not turn into breeding groups for plant-eating slugs and snails.
Beware: Sour Mulch
Mulch should normally smell like freshly cut wood, but sometimes will develop a toxicity that will cause it to smell like vinegar, ammonia, sulfur or silage. This happens if the material is not rotated often enough and it forms pockets where no air is circulating. When this occurs, the decomposition process become anaerobic and produces these toxic materials in small quantities. Once exposed to the air, the process quickly reverts back to an aerobic decomposition, but these toxic materials will be present for a period of time. If the mulch is placed around plants before the toxicity has had a chance to dissipate, then the plants could very likely be severely damaged or killed depending on their hardiness. Plants that are predominantly low to the ground or freshly planted are the most susceptible.
If sour mulch is applied and there is plant kill, the best thing to do is just water the mulch heavily. Water will help the chemicals to dissipate more quickly and refresh the plants. By the time plant kill is noticed, most of the toxicity will have already disappeared anyway, so removing the offending mulch will have little effect. While testing after plant kill will not likely turn up anything since the toxicity will have dissipated, a simple pH check may reveal a highly acid content, perhaps in the 1.8 to 3.6 range instead of the normal 6.0 to 7.2 range. Finally, placing a bit of the offending mulch around another plant to check for plant kill will verify if the toxicity has departed. If the new plant is also killed, then sour mulch is probably not the problem.