2. General Mineral Deficiency Symptoms of Plants.

3. Application and Storing Fertilisers.

4. Plants and their Needs.

GENERAL MINERAL DEFICIENCY SYMPTOMS OF PLANTS
(Compiled from various sources)

NITROGEN - Slow growth of top and roots; leaves turn yellow-green when young to orange, red or purple when mature (veins may turn purple), beginning from bottom leaves to top; reduction in number of flowers and yield of grain or fruit; slow growth and delay of opening of buds.

PHOSPHORUS - Similar to nitrogen deficiency but leaf colour either dull bluish green with tints of purple instead of yellow or red, OR leaves dull bronze colored with purple or brown spots (leaf edges often brown, especially in potatoes).

POTASSIUM - If mild deficiency, stems thin; if severe, stems stunted or die; leaves usually dull bluish green, often yellow streaks between veins, followed by browning of tips and edges, and development of brown spots near edges; leaves rolled (begins at lower leaves); poor root growth; poor development of flowers and grain or fruit.

CALCIUM - Begins at upper leaves; leaves very distorted and curled at edges; edges appear ragged and leaves may have thin yellow bands or be brown, then die roots poorly developed.

MAGNESIUM - Leaves turn yellow (sometimes between veins, sometimes in spots or streaks), then turn brown and die (starting at bottom of plant); grain or fruits poorly developed.

MANGANESE - Similar to magnesium but starts at top of the plant.

SULFUR - Reduction of growth; curling down of leaves at tips; similar to nitrogen deficiency except that lower leaves are not lost.

BORON - Begins at upper leaves; leaves become light green (lighter at base, veins turn purple, leaves may have faint streaks and yellowing, then turn orange) and stop growing, root down at tip, with tissue breakdown at base, poor growth of tops and roots; flower buds drop off; no grain or fruit.

IRON - Severe yellowing of newer leaves (either spotted or total); more often visible in trees than yearly crops.

ZINC - Molted spots on leaves, first yellowish, then yellow or purple-red (appears late in summer, then leaves drop early), leaves become crinkled and small.

MOLYBDENUM - Similar to nitrogen deficiency, since molybdenum is necessary for nitrogen-fixing bacteria; leaves becoming yellow between veins, first on mature leaves, then to younger; young leaves may become severely twisted and eventually die.

NITROGEN in biological life is an electrolyte. As an electrolyte in the soil, nitrogen functions very much like a metal carrying an electrical charge. It is the element that ionises the water in the soil and make it possible for the minerals to get into the plant. Therefore, without nitrogen in the soil the electrical currents could not flow and the process of ionisation, by which plants are built, could not take place.

PHOSPHATE in the soil is the factor that determines the mineral content in any plant. The higher the water soluble phosphate the higher the mineral content. In order to get the maximum yield, the proper amount of phosphate is necessary. A great deal of phosphate used on farms today comes from Florida.

POTASH determines three basic things in a plant. It determines the thickness of the leaf and the thickness of the stem. The second thing it determines is the number of fruit sets on a plant and is the binder that holds the fruit to the stem. Thirdly, it determines the size of the fruit.

CALCIUM was once considered to be a secondary or minor nutrient for plants. However, we have learned in recent years based on research and its importance to the plant that it is now classed as a primary or major nutrient. By weight and by volume, plants need more calcium than all other plant foods put together. Calcium is the element that can increase the volume of a crop more than any other element.

pH of the soils varies however, most soils are between 4.5 and 8.0. pH is determined on a scale of 1.0 to 14.0 with 7.0 being neutral. A reading of 1.0 to 7.0 are acidic and the lower the reading away from 7.0 the more acidic the soil. Readings from 7.0 to 14.0 are the alkaline and the higher the readings from 7.0 are more alkaline. pH can be adjusted in the soil using calcium (lime) to raise it and the sulfur to lower it. Keep in mind that if the organic matter in the soil is good it will buffer the pH that might affect the plant.

Plants need water, in fact all the chemical reactions that take place in the plants require the presence of water. All movement of nutrients through the plant and the soil require water. Water also aids in giving the plant firmness. Too little water and the plant will wither, on the other hand too much water and the roots will be starved of oxygen and rot. Young plants need a bit more water to help build new root systems. Many also need more water when they set their flowers or when fruit and vegetables are maturing. Keep in mind that soils rich in organic matter hold moisture well, but release any excess to a deeper holding level in the subsoil structure for later use by the plant. If the rainfall is less than one (1) inch for week, additional watering will be required for most crops.