Question

Potted plants may die if they get too much of a good thing. With what you now know about water relations in plants, why might it be harmful to a plant to have too much soluble N, P, and K applied to its container?

Answer 1

Effects of excess nitrogen: Excess nitrogen leads to increase in foliage of plants. It will cause increased growth of leaves and stems but the growth of flowers and fruit will be reduced. As a result the plant will not be able to produce reproductive organs during the growing season.

Excess nitrogen also reduces the strength of the stems.

Plants with excess nitrogen are more susceptible to insect attacks.

The roots have limited growth as all the nutrients are directed to the shoot system.

Effects of excess Phosphorus: excess phosphorus results in leaf chlorosis because it reduces the plants ability to take up iron, manganese and zinc.

It also causes excess weed growth and stunted plant growth.

Excess phosphorus also decreases the growth of mycorhizzae which are beneficial to the plant.

Effects of excess Potassium: Excess of potassium hampers the absorption of iron, magnesium, iron and zinc. This will leads to symptoms present in the deficiency of these elements.