Soil Science: Too Much of a Good Nutrient Can Be Bad
If essential nutrients are really essential for healthy plant growth and development, more is better, right? Not so fast. We’ve all heard warnings about high-nutrient fertilizers having the potential to “burn” young plants. This is particularly true for chemical fertilizers, which contain a lot of salt. What shows up as burned foliage on a plant is the result of the excess salts in the fertilizer drawing the water out of the young plant, robbing it of its needed hydration.
Phosphorus is the macronutrient that is most likely to be oversupplied by fertilizer, so it is important to have your soil tested to be sure that you really need additional phosphorus. In some states, it is actually illegal to fertilize a lawn with phosphorus unless you have a soil test that shows you need it, because phosphorus runoff has caused accelerated algae bloom in many lakes and rivers. Excess phosphorus interferes with nitrogen uptake in plants and can tie up other micronutrients in the soil, making them unavailable to plants and causing stunted growth. Potassium can also be over-applied, and can also limit nitrogen uptake.
Magnesium and Calcium interfere with each other, so when one of these micronutrients is present in too high a concentration, it prevents the uptake of the other one. Excess calcium in the soil also raises soil pH. On the other hand, excess manganese and copper are often present in highly acidic soil and can cause young leaves to lose their green color.
So how do you avoid over-fertilizing and providing toxic levels of nutrients? Test your soil, of course. Beyond that, using natural & organic fertilizers like Garden Maker Naturals are your best tool. Because most of the nutrients in organic fertilizer ingredients need to be cycled through soil microbes before they’re ready for plants to use, the nutrients tend to be released over a longer time period, preventing over-concentration. These ingredients also contain fewer salts than chemical fertilizers, so they are less prone to drawing the water out of plants. Natural and organic fertilizers are very forgiving, nutrient-wise, and feed the important soil microbes that do the hard work of building long-term soil fertility. So work a little organic fertilizer into your soil, then relax and let nature do the rest!