It is a good idea to have your soil tested to know the nutrients needed for plants to grow in your garden. Soil testing results will provide the information you need to know how much lime and fertilizer your plants need.
Vital Nutrients Plants Require for Growth
The basic needs that make plants grow are:
- Water
- Air
- Light
- Suitable temperatures
Water and air provide plants with three necessary nutrients: carbon, hydrogen, and oxygen; however, in the soil there are several nutrients needed for healthy plant growth. These nutrients are divided into two major groups and are arranged according to the quantities needed by plants.
Macronutrients
Macronutrients are elements that plants need larger quantities of to grow.
- Nitrogen: Leaf and stem growth are dependent on nitrogen. Insufficient nitrogen reduces growth and leaves turn a pale yellowish-green. Wet and cold soil dilute nitrogen. Too much nitrogen in the soil creates a potassium deficiency.
- Phosphorus: Critical in the germination and growth of seeds, flowers, fruit, and roots, too much phosphorus may lead to potassium deficiency. When phosphorus is deficient, growth is reduced and leaves fall off prematurely. Plants lacking phosphorus produce dull, bluish-green leaves that turn a purplish or bronze color with brown edges.
- Potassium: Potassium promotes hearty, disease-resistance growth. Without adequate potassium, growth is stunted and leaves grow close together. Leaf tips and edges become brown and edges curl. Too much potassium can lead to calcium and magnesium deficiencies.
- Calcium: A vital component in cell walls of plants, calcium is essential to root growth. Without adequate calcium roots develop poorly and leaves become distorted and turn brown.
- Magnesium: Necessary for chlorophyll production, magnesium plays a vital role in most enzyme reactions. A magnesium deficiency causes varying symptoms in different plants that include, yellowing leaves that suddenly fall off without withering. Too much magnesium can cause a calcium deficiency.
- Sulfur: Sulfur is necessary nutrient for chlorophyll formation. Too little sulfur produces slow growth that generates small round leaves that are stiff and brittle. Leaves drop and tip buds die.
Micronutrients
Micronutrients are those elements that plants need lesser quantities of, but are still vital to plant health.
- Iron: This trace element is needed for chlorophyll formation and oxygen transfer. Without adequate iron, leaves yellow (but leaf veins remain green). If you add too much lime to your soil, it can lead to an iron deficiency.
- Manganese: A channel for a variety of enzymes, manganese is essential for chlorophyll formation. Too little manganese causes a variety of indicators depending on the type of plant. The most common signs include yellowing leaves with green veins or grayish-white specks that appear on the leaves. Too much manganese may deplete iron in the soil and cause symptoms similar to those exhibited with a lack of manganese.
- Boron: Boron conveys the interchange of sugars, for reproduction and the cells' ability to intake water. Plants suffering from a deficiency of boron become distorted and form hollow stems along with malformed fruit. Other symptoms include curled leaves that appear scorched and can even develop mottled leaves.
- Zinc: Important for the production of proteins, zinc affects how big plants grow and mature. Lack of zinc produces less fruit and brings about yellowing of leaves between veins often accompanied by purple or dead spots with small, deformed leaves growing close together.
- Copper: This is another nutrient important for the production of proteins and plays and important role in reproduction. If your plants don't get enough copper, they will display bluish-green leaves that might wither or never unfold. Lack of copper may also form rosettes on growing tips.
- Molybdenum: This nutrient is vital to nitrate enzymes. It supports the formation of bean and pea root nodules. Inadequate amounts of molybdenum can cause leaves to develop dead spots or yellow mottling. The growing tips sometimes die or become distorted.
- Chlorine: Lack of the right amount of chlorine in your soil might affect carbohydrate metabolism and photosynthesis. This deficiency leads to stubby roots and wilting.
Lesser Know Micronutrients
A few plant nutrients important to some plant growth are lesser known and a couple recently designated as essential.
- Silicon: Recognized as a beneficial substance, silicon isn't listed as an essential element for the growth of plants. However, this element may become taxed and depleted when a plant is under stress.
- Sodium: As an essential micronutrient element sodium's role is important for plant metabolism in blue-green algae, sedges and some flowering plants.
- Cobalt: Recently recognized as a possible essential nutrient for plant growth, cobalt is rarely needed as a supplemental nutrient. Nitrogen fixation within legume nodules is dependent upon cobalt.
- Nickel: Until recently, nickel wasn't listed as an essential element for plant growth. The requirements are so low that most soils and water provide enough for plants. When a plant is deficient in nickel, it doesn't exhibit any symptoms. Nickel amounts are rarely tested or added to fertilizers.
Test Soil before Adding Nutrients
Plant growth is dependent on the right nutrients. A soil test will reveal if any nutrients are lacking and if any supplements are needed.