Plants mostly get their nutrients from the soil. Depending on the soil condition will determine the rate of growth and yield from your plants. Soil testing will provide you with a measurable indication of what your soil is missing. The result will provide the pH states, guiding how to provide the right fertilizer to your garden.
Another way to determine your soil nutrient deficiency is by looking at your current plant color and structure. The visual cues indicate what your plant is missing. This method can be subjective, but these cues can be used in conjunction with a soil test
What is soil deficiency?
Soil deficiency is a need for proper nutrients in potting and garden soils. The soil nutrient deficiencies cause the poor development of plants and flowers. Proper use of nutrients can control plants’ growth rate, form, and character.
Nitrogen is the most critical nutrient in this regard. If tomatoes are fertilized heavily with nitrogen, the plants will have abundant vines but little or no fruit.
Different levels of nutrient level cause plants to underdevelop and produce less than desirable results.
For this reason, it is essential to plant crops with similar nutrient needs close together to avoid improper timing of fertilizer applications.
Applying nutrients late in the growing season to plants and shrubs usually causes them to produce a flush of new growth. Such plants should instead be moving into dormancy. The delay of dormancy can cause severe cold temperature damage to the new growth in the winter.
How to Identify Nutrient Deficiency?
Nutrient deficiency can be assessed by carefully assessing the rate of growth of plants and the development of plant leaves. Plants respond unfavorably to deficiencies of nutrients and to some excesses too.
What are primary nutrients and signs of deficiencies?
Nitrogen deficiency: The leaves turn pale green to yellow. The oldest leaves are affected first, but the whole plant may be yellow in severe cases. Growth is usually stunted.
The high rate of nitrogen fertilizer causes the excess occurrence of nitrogen. The result is the excess vegetative growth and poor fruit growth.
Phosphorous deficiency: Leaves appear reddish-purple. The oldest leaves are affected first. Plant growth is stunned. Common in strongly or highly acidic and alkaline soils or these soils low in phosphorous.
It also occurs in cool wet soils in the spring. Plants may grow out of phosphorous deficiency as the soil warms.
Potassium deficiency: Leaves become gray or tan at or near the margins. The oldest leaves become affected first, with characteristic scorching symptoms around the leaf margins. It is most common on sandy soils and soils low in native potassium.
Too much potassium does cause the salt burn. Soils with high potassium levels can induce magnesium deficiency.
What are secondary nutrients and signs of deficiencies?
Calcium deficiency: The signs include plant growing points dying. Younger leaves are affected. Root tips die, and root growth is slow. Tip burn of cabbage, cauliflower, and lettuce and blossom end rot of tomatoes due to localized Calcium deficiency within the plant. Most common on acid and droughty soils
Magnesium deficiency: The oldest leaves on the plant turn yellow between the veins. Younger leaves may be affected severely, and older leaves drop off.
It may occur in acid soils, sandy soils, or soils with high potassium levels.
Sulfur deficiency: The symptoms are quite similar to nitrogen deficiency, except that the youngest leaves are usually affected first. Most common in sandy soils low in organic matter.
What are the micronutrients and signs of deficiencies?
Boron deficiency: Usually occurs in younger parts of plants. Growing points die. Leaves appear distorted. The appearance of hollow stem and internal browning in cauliflower and broccoli cracked stem in celery, and internal browning in beets and turnips.
Excess application of boron in soils can be highly toxic to some plants at low levels. Avoid excessive Boron application.
Chlorine Deficiency: Excess application of Chlorine in soils does lead to leaves being scorched. In the winter months, when Chlorine is used for defrosting snow and ice. Plants located near streets and treated pavements are affected by Chlorine.
Copper Deficiency: Lack of copper nutrients in soils results in yellowing or die-back of youngest leaves. Most copper deficiencies occur in organic soils. Excessive copper application can happen due to the continuous use of copper-containing fungicides.
Iron Deficiency: Low iron content in soils leads to yellowing between the veins on the youngest leaves while veins remain green. Low iron in soils frequently occurs on soils with a pH greater than 7.2. Some plants are more susceptible than others.
Magnesium Deficiency: The deficiency is usually indicated by yellowing between the veins of the youngest leaves. Usually, the prominent veins remain green and cause a fishbone-like appearance.
In some plants, older leaves may develop gray streaks or dots. Occurs mainly in soils with a pH greater than 7.2. It can also occur on organic soils with a pH greater than 6.0.
Molybdenum Deficiency: The deficiency is usually indicated by pale, distorted narrow leaves. Causes “whip tail” of cauliflower. It usually occurs on soils with a pH of less than 5.0.
How to apply fertilizers on potted plants:
Typically the fertilizer accumulates on the top of the soil container and forms a yellow to white crust. A ring of salt deposits may also form around the pot. The best way to prevent injury from fertilizer salts is to prevent their accumulation by proper watering.
When watering, always allow a volume of water equal to at least 1/10 the volume of the container to drain through. Make sure to drain the drip plate to prevent reabsorption of the drained water and its salts by the soil.
To prevent further accumulation of fertilizer salts, the container that grows the plants should be thoroughly leached every four to six months. The process can be done by slowly pouring an amount of water equal to about twice the volume of the container,
Allow the water to drain completely. Replace any salty crusts with no more than one-quarter inch of the underlying soil before leaching. It is best not to add more soil to the top of the container. If the salt level is exceptionally high or the container lacks drainage, repot the plant with new soil.
How to apply fertilizers on gardens and lawns:
Although rear, over-fertilization in gardens and lawns with fertilizers occurs with excessive fertilizers. To remedy this problem, water the lawn with at least two inches of water as soon as possible.
This will dilute the fertilizer salts by dispersing them throughout several inches of soil. Also, keep the soil moist by frequent watering to prevent further concentration of fertilizer salts. Excessive amounts of manure and wood ash can also cause soluble salt problems.