A soil nutrient program is important to produce top quality vegetables. But adding too many nutrients to the soil can have the opposite effect. Have you heard of root burn? It is just one of the things that can go wrong if you add too much fertilizer to the soil.
But before we see how over addition of nutrition affects plants, let’s see the difference between fertilizers and soil amendments.
Are Fertilizers the Same as Soil Amendments?
Many people are confused about the difference between fertilizers and amendments. Fertilizers consist of soluble salt compounds, and they directly affect the growth of soil. Soil amendments affect plants indirectly by improving the chemical and physical properties of the soil. Next, let’s discuss why you should be worried about fertilizer burn.
Fertilizer burn causes plant foliage to become scorched. Fertilizer burn is related to root burn, where the roots get damaged. To understand fertilizer burn better, you must know how plants take in water and nutrients.
In the natural condition, soil has a greater concentration of water than roots so there is a difference in water pressure. The water molecules move from the soil, across the semipermeable membrane of the roots to establish equilibrium which benefits the plants.
On the other hand, when there is too much fertilizer in the soil, the status quo is disturbed. Now, there is more water in the roots than the soil around. Water moves from the roots into the soil, causing the plant to become dehydrated. Dehydrated plants lose their turgor and start to wilt.
More Dangers of Over Fertilization
When you add too many fertilizers to the soil, soluble salts start to accumulate in the soil. This not only alters the soil, but it also kills beneficial microorganisms.
It may also lead to a sudden growth spurt in the plant. At the same time, the roots are not developed enough to benefit from this oversupply. So they are not able to transport nutrients to the plant.
Moreover, synthetic fertilizers are not natural to the soil. The soil does not have the constitution to take in artificial fertilizers. So when there is too much fertilizer in the soil, it does not dissolve by rainfall or even irrigation water.
Instead, you have evaporation. The salts stay behind and the soil becomes altered. The salinity of the soil is raised and the pH is lowered. Low pH is not a good thing because the plants can’t take in the nutrients.
Root Rot, Defoliation and Other Dangers
Over nutrition causes other injuries to plants. Plant roots have to exert pressure to pull water and nutrients from the soil. But over nutrition causes the roots to become shriveled because of osmosis. Root rot sets in and the plant becomes more susceptible to root diseases.
At this point, the leaves start yellowing and the root tips and the margins become brown. Defoliation begins and the plant stops growing.
Over nutrition can also cause plant stress. Plant stress weakens the plant and makes the plant more vulnerable to diseases and insects, especially those that suck plant sap.
Why It Is Important to Get the Soil Tested?
Before you add nutrients to the soil, you should get the soil tested. This will help you know what nutrients are lacking in the soil. If you can avoid adding fertilizer, this is even better. Soil amendments, like vermicompost, organic compost, alfalfa, cured manures, and bone meal, are an excellent alternative.
If you have to use fertilizers, use natural, organic fertilizers. They release nutrients more slowly. Non-organic, commercial fertilizers are not recommended and they are in concentrated form. This fertilizer increases the risk of plant damage and the death of beneficial microorganisms.
This is why we are very careful when we add nutrients and soil amendments to our custom soil mix so that we can produce healthy and nutritious vegetables.