FERTILIZING

PART 1 – Fertilizing Requirement and Uptake

INTRODUCTION

Turfgrass constantly renews itself through the normal growth process. New roots, buds, rhizomes, tiller and leaves replace the old, diseased and worn. Fertilizers are designed to give the turfgrass the right balance of nutrients which promotes this renewal for healthier growth, improve root development and replace nutrient loss by leaching, fixation, volatilization and also clipping removal.

NUTRIENT REQUIREMENT

Anyone who has ever grown plants knows how much difference fertilizing makes. Most of the time, it’s a positive difference, but many gardeners have also learned that too much fertilizer can kill the plants. There are three commonly applied nutrients which are Nitrogen (N), Phosphorus (P), and Potassium (K), but plants also need 13 other essential nutrients to grow.

NUTRIENT UPTAKE

The essential elements for plants growth must be present in the proper amounts and the proper proportion to one another for optimum growth and development to occur. Nutrients can be absorbed into the plants through the leaves, stems, and roots.

The total quantity of nutrients contained in most soils is high however, a major portion of these nutrients is tightly bound in unavailable forms. Only nutrients contain in the soil solution are available for uptake by the turf grassroots. The turf grassroots system is ideally suited for nutrient uptake because of a fibrous, extensive roots system that is surrounded by the soil solution containing nutrients. Once absorption has occurred, the nutrients are translocated to the actively growing tissues of the plants.

FACTORS INFLUENCING NUTRIENT UPTAKE

1. Nutrient uptake is determined by the characteristics and conditions of the root system and surrounding soil. The depth and extent of the root system are important factors influencing nutrient uptake.
2. A second factor is the energy available from the roots respiration. Adequate respiration rates are maintained by ensuring

a .Adequate oxygen supply.
b. Satisfactory levels of respiratory substrate.
c. The optimum temperature for root activity.

3. Poor soil aeration or waterlogged soils severely restrict respiration and impair the update of essential nutrients.
4. Externally, the soil moisture content is important because it influences the ion diffusion rate into the outer space of the roots. The hydrogen ion concentration is an important external factor influencing nutrient uptake. The concentration of certain nutrients declines in the soil solution with increases in acidity or alkalinity.
5. Foliar feeding is the practice of introducing nutrients through the leaves. Application levels are typically less than those us for soil – applied granular applications.

Media Department; The RS Group