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PARASITE

A parasite is an organism that lives on or inside another host, without benefiting the host.

PARTS PER MILLION (PPM)

Parts per million is a scale used to measure the strength of nutrient in a solution. 

PASSIVE

A hydroponic system that delivers water and nutrients to plant roots through absorption or capillary action is passive. Hand feeding plants with water and nutrients into trays or pot saucers and allowing plants and medium to absorb solution is passive feeding.

PATHOGEN

A pathogen is a micro-organism (germ) that causes diseases and is harmful to plants, usually bad bacteria, fungi and viruses. Growing media can be a common place for harbouring pathogens.

PERENNIAL

A plant that completes its life cycle over several years is perennial.

PERLITE

Perlite is a growing media that is made from volcanic rock, heated to extreme temperatures to produce very small lightweight glass pebbles. Perlite can be used alone or mixed with soil to aerate the media, and perlite also holds water and nutrients well. 

PHOSPHORUS (P)

Phosphorus is a macronutrient that is used by plants to aid metabolism and transfer energy and also plays a major role in flower formation.

PHOTOPERIOD

The photoperiod is the hours of light received by plants, compared to the hours of darkness received by plants.

PHOTOSYNTHESIS

Photosynthesis is the building of chemical compounds when plants absorb energy from light, water and Co2.

POTASSIUM

Potassium is a macronutrient that is used in larger amounts when flowering plants to help sugar production, essential for the development of large vibrant flowers.

POTENTIAL HYDROGEN (PH)

A solution can be acidic or alkaline. PH (potential hydrogen) is used as an indicator of how acidic or alkaline a solution is. The PH scale ranges from 0-14, a solution with a PH value of 7 is neutral, below 7 to 0 is acidic with 0 being very acidic and above 7 to 14 is alkaline with 14 being very alkaline. Maintaining the correct PH level is critical for soil and hydroponically grown plants, as they will easily absorb all nutrients with the correct PH level maintained for the type of plant grown.

PRIMARY NUTRIENT (NPK)

The primary nutrients essential for plant growth are nitrogen (N), phosphorus (P) and potassium (K).

PYTHIUM

Pythium is a fungal disease.

 



Last Updated (Friday, 30 August 2013 19:14)