Understanding your soil’s pH and the best way to handle it are secrets to successful gardening. Soil pH affects nutrients that control plant health and growth. If your garden soil tested at 7.5 pH, it is just above the neutral point of 7.0. Before you begin adjusting soil pH, understand what your soil results imply for your own garden and its plants. Depending upon your gardening objectives, that soil pH might be precisely where you need it.
Interpreting Soil Results
When thinking about soil test results, don’t believe in absolutes. Several factors affect pH, such as seasonal variations. Soil type and composition, biological activity, organic matter, soil salts and soil moisture all affect your results. A dried-out sample yields different results than the same sample moist. Variability comes with the territory. The pH scale runs from 0.0 to 14.0, with pH under 7.0 considered progressively more acidic and pH above that mark deemed increasingly alkaline. The University of California advises the accuracy of soil pH readings is either plus or minus 0.5 pH units. In other words, your 7.5 soil might be anywhere between 7.0 and 8.0.
Realizing Soil pH
The best soil pH level for the lawn is based upon the plants you want to grow. For plants to utilize soil nutrients — naturally present or added through fertilizers — the enzymes have to stay soluble. Because pH changes, reactions happen that limit a plant’s ability to absorb certain nutrients. Many components, such as iron and iron, stay most accessible plants in low-pH, acidic soils. Plants that need those components in bigger quantities suffer in alkaline soil, but those plants are exceptions. Most plant nutrients reach their peak access in near-neutral soil pH. That range from 6.5 to 7.5 is the perfect soil pH for most plants.
Lowering Soil pH
Common garden clinics like adding organic matter and using fertilizers lower soil pH gradually. Base major changes only on recommendations from a respectable soil laboratory. Products and amounts depend on your soil’s specifics. Incorporating elemental sulfur, for example, in the top 6 inches of soil at a speed of 1/2 pound per 100 square feet lowers pH from 0.5 unit at loamy soil. Sandy soils, however, only need one-third that amount, while clay soils may take nearly double. Overdoing pH adjustments can leave soil toxic, so follow recommendations carefully. Wear protective clothing, such as gloves and safety instinct, whenever utilizing substances, and prevent all contact with exposed skin.
Living With Alkalinity
Trying to remain naturally alkaline soil in acidic pH ranges is an endless battle. Alkalinity, typical in arid regions, comes as indigenous stone weathers and low precipitation fails to clean elements away. These natural processes always replenish soil’s alkalinity. Think container growing to get plants that require acidic soil. For many other plants, 7.5 pH soil might be perfect. Several drought-tolerant plants, dry-region natives and Mediterranean natives prefer slightly alkaline soil pH. Align your lawn plans with your soil, and you’ll jump the need for constant soil alterations.