There are three main elements required for healthy growth
Nitrogen: For healthy green leaves, stem growth (cotton seed meal, fish meal, fish emulsion). Plants that are nitrogen deficient won’t be as green.
Phosphorus: For good root growth and fruit/seed production. There is no phosphorous in the atmosphere. As rocks break down and erode, they release phosphorous into the soil where it can be absorbed by plants. Comfrey and Mexican sunflower are fast-growing phosphorus fixers.
Potassium: For disease resistance and healthy growth (wood ash)
There are many more elements needed, those are discussed below.
Plants need many nutrients to grow and thrive. Plants use their roots to soak up water and minerals from deep down in earth and moves them up the plants stem to reach the leaves and other parts of the plant. Once the plant dies, these nutrients will leach back into the Earth to improve your soil.
When farmers and gardeners use chemical phosphorous on their plants, the excess runs off into waterways and causes algal blooms which is the extreme growth of algae. This algae is so thick that it blocks sunlight to the plants and animals below. As the algae dies, it attracts bacteria which uses all the oxygen in the water and eventually kills fish, snails and other aquatic plants and animals. Be smart about the way you use phosphorous.
Secondary Plant Nutrients
The secondary nutrients needed are Calcium (C), Magnesium (Mg), Sulfur (S)
- Calcium: Promotes growth of young roots and shoots, builds cell walls. Plants that are calcium deficient will show it in the new growth. The new leaves will have deformities, shrivel up and die.
- Magnesium: Helps a plant take in the nutrients it needs, helps form seeds and is a part of the chlorophyll. Leaves on plants that are magnesium deficient will turn yellow with highlighted veins.
- Sulfur: Maintains the dark green color because it helps manufacture chlorophyll. Most soils contain the sulfur that plants need.
Trace Elements
Trace Elements are the nutrients that plants need in smaller doses, but they are still incredibly important! These trace elements include Boron (B), Chlorine (Cl), Copper (Cu), Iron (Fe), Manganese (Mn), Molybdenum (Mo), Zinc (Zn)
- Boron: Important for cell development, plant metabolism and hormones. Only small amounts of boron are needed, and can be toxic in large doses. Plants that are boron deficient are fairly easy to identify as it leaves spots of yellow on the leaves in between the veins.
- Chlorine: Helps in the photosynthesis process. Most soils contain the chlorine that plants need. Plants that are chlorine deficient look similar to those with nitrogen deficiencies, with yellowing between the veins.
- Copper: Important for chlorophyll. Copper will give your veggies flavor and flowers their color. Plants that are copper deficient are lighter in color. the new leaves will be damaged and the leaf nodes will be closer together causing the plant to be shorter.
- Iron: Also helps a plant make chlorophyll. Plants that are iron deficient are yellow with highlighted green veins.
- Manganese: Also involved in photosynthesis. Plants that are manganese deficient will turn a deep pale yellow.
- Molybdenum: Allows a plant to use the nitrates it absorbs from the soil. Without enough molybdenum, a plant will not have enough nitrogen. Plants that are molybdenum deficient will have a stunted growth.
- Zinc: Used to develop enzymes and hormones. The leaves of plants that are zinc deficient will turn white around the edges.