Normally when plants are grown in fertile soil, fortified with compost and organic fertilizers, or fresh potting soil, they do not suffer from nutritional problems. However, disorders do arise when a plant variety has particular needs or when too little or too much fertilizer is used. A fertilizer overdose can be remedied by flushing with water. Plants with specific needs like acidic soil or a particular nutritional deficiency require the addition of fertilizer.

Too much nitrogen produces dark green foliage, little or no flowers or fruits, and burnt leaf tips. Too little nitrogen makes light green to yellow leaves and slow growth, especially in the lower leaves of older plants.

An excess of phosphorous is rare, yet when it does occur symptoms are similar to an excess of nitrogen. A phosphorous deficiency is revealed by deep green, red or purple leaves, few blooms and fruits, yellowing bottom leaves, and stunted growth.

Potassium toxicity will create nitrogen, phosphorous and trace mineral imbalances. Potassium deficiency produces very tall plants with weak stems as well as leaf tips and edges turning yellow, then later brown.

Trace mineral overdoses of calcium and magnesium increase potassium problems. Too little calcium will cause young leaf tips to die back, blossom end rot on tomatoes, short roots, stunted growth, and rotten plant centers. Magnesium deficiencies show up in leaf tips turning brown and curling upwards in a hook.

Plants may also reveal problems when the soil pH is off. Soil pH measures whether a soil is acid or alkaline on a scale of 1 to 14. While most plants prefer a neutral pH of 6.5 to 7, acid lovers like blueberries enjoy a pH of 4.5. The pH regulates nutrient uptake to plants, and if imbalanced will lock up vital nutrients in the soil even if they are in adequate supply. To raise the pH add oyster shell lime or liquid calcium. To lower the pH use Sul-Po-Mag (K-Mag) or powdered sulphur. An abundance of organic matter in the soil will help plants accept a wider range of pH.

Ecological Pest Control

Simply growing plants in a healthy garden with soil empowered by compost and organic fertilizers and amendments greatly reduces attacks by pests and diseases. Further protection for plants against problems can be provided by growing cover crops and companion plants to repel or trap pests, growing flowers and flowering vegetables to attract beneficial insects, and using sprays and powders made from natural materials.

Elements for Optimum Growth

There are 19 beneficial elements which contribute to healthy plant growth. Three of these essential elements: oxygen, hydrogen, and carbon, are provided by air and water while the rest are absorbed by plants through the soil.

• Boron (B) Stimulates cell division, flower formation and pollination.
• Calcium (Ca) Raises soil pH; promotes root hair formation and early growth.
• Chlorine (Cl) Needed for photosynthesis; stimulates root growth and aids water circulation in plants.
• Cobalt (Co) Improves growth, water circulation, and photosynthesis.
• Copper (Cu) Stimulates stem development and pigment formation.
• Iron (Fe) Stimulates the formation of chlorophyll and helps oxidize sugar for energy; also necessary for legume nitrogen fixation.
• Magnesium (Mg) Aids in chlorophyll formation and energy metabolism; it increases oil production in flax and soy beans; helps regulate uptake of other elements.
• Molybdenum (Mo) Needed for nitrogen fixation and nitrogen use in the plant; stimulates plant growth and vigor much like nitrogen.
• Nitrogen (N) Necessary for chlorophyll and genetic material (DNA & RNA) formation; stimulates green, leafy growth.
• Phosphorous (P) Necessary for genetic material (DNA & RNA) formation; stimulates fruit, flower and root production, and early season growth; increases disease resistance.
• Potassium (K) Produces strong, sturdy plants with thick cell walls and increases disease resistance; stimulates fruit, seed and root production.
• Silicon (Si) Increases number of seeds; strengthens cell walls of plants
• Sodium (Na) Increases resistance to drought; increases sugar content in some crops.
• Sulfur (S) Aids in formation of certain oil compounds that give specific odors to some plants such as onions, garlic, mustard, etc; increases oil production in flax and soy beans.
• Manganese (Mn) necessary for the formation of chlorophyll.
• Zinc (Z) Stimulates stem growth and flower bud formation.