RHS Practical Level 2 - Random Terms n Bits

Mineralisation

Breakdown of organic matter by soil organisms

Soil pH

A measure of acidity or alkalinity of soil, which has an effect on soil nutrient availability, disease occurance, biological activity in the soil, and the plant choice for the area.

Neutral soil is usually optimum pH for plant growth.

0-6 = Acidic

7 = Neutral

8-14 = Alkaline

Can be measured using a chemical regent test or electronic pH probe.

Soil electro-conductivity

A measure of dissolved salts or irons which is an indicator of the level of nutrients in the soil.

Measured in millisiemens per centimeter:

0.8 = low nutrient level

1-3 = normal

4+ = high

Some soils have a naturally lower reading e.g sandy soil.

High nutrient concentration can lead to root scorch through reverse osmosis.

Vegetative propagation

A type of asexual reproduction where a new plant grows from a fragment of a parent plant e.g a cutting or rhizome suckers - the offspring is a genetic clone and so the characterisitcs are retained

Timing of taking cuttings for propagation

Softwood = Spring

Semiripe = Summer

Hardwood = Autumn

Leaf cutting = Spring-Summer

Division = Early Spring or early Autumn

Plant Disorders and Diseases

A disease is an impairment in structure or function caused by a living organism (pathogen), while a disorder is a deviation from normal function caused by non-living factors like environmental or nutritional imbalances.

Essentially, diseases are infections, while disorders are caused by environmental or physiological issues.