How can an extra amount of nitrogen, phosphorus, or potash be given when a plant requires it?

Just dilute the necessary element in water, and apply. To give extra nitrogen, mix 1 tablespoon of nitrate of soda in 1 gallon of water. To give extra phosphorus, mix 1 1/4 tablespoons of superphosphate in 1 gallon of water. To give extra potash, mix 2 to 3 tablespoons of wood ashes in 1 gallon of water. If the plants require acidic soil, mix 1 teaspoon of muriate of potash in 1 gallon of water instead of wood ashes.