Calcium influences the water movement in cells and is necessary for cell growth and division. Calcium also activates enzymes, and some plants will require calcium to help take up nitrogen and other minerals. Calcium can easily be leached (flushed) from plants and media if required.
To calibrate, is to test and reset measuring instruments (PH, EC meters) using a solution that is fixed to a required level. Most meters are simple to calibrate with the touch of a button, and held in the required solution they will reset themselves to the desired level. Calibration of meters should be done regularly to ensure accurate readings are being taken from your nutrient solution, to avoid any problems occurring. A meter not cleaned and calibrated regularly, can obviously mislead the grower and result in optimum nutrient and PH levels not being maintained.
Sugar, starch and cellulose are all carbohydrates. It is a neutral compound of carbon, hydrogen and oxygen formed by green plants.
CARBON DIOXIDE (CO2)
Carbon Dioxide (CO2) is a colourless and odourless gas that occurs naturally in our environment. Additional Co2 can be provided in grow rooms to increase photosynthesis, making your plants grow faster and larger. This requires a good quality CO2 unit to regulate and disperse the correct levels of CO2 into your grow room at the correct time, and of course a bottle of CO2. Set up and used correctly, CO2 can increase growth and yield by 30-40%.
Celsius is a scale for measuring temperature, e.g. 0 degrees Celsius, water freezes and 100 degrees Celsius, water boils.
Chelate is a process of combining nutrients, to allow plants to easily absorb and take up metal ions in the nutrients, through their roots.
Chlorine is a chemical element used to purify water. Tap water should be left for 24 hours before using, to help remove the chlorine.
Chlorophyll is a group of pigments within plant cells that absorb light energy and give a vibrant green colour to most plants. Chlorophyll is found in the chloroplasts of a cell and is necessary for plant photosynthesis.
Chlorosis is the condition of a sick plant with yellowing leaves, normally caused by a nutrient deficiency or an imbalanced PH level. Leaves produce insufficient chlorophyll, and this makes leaves turn pale, yellow and white. Plants may die from chlorosis, unless the cause of its insufficiency is treated.
A section of plant taken from a donor plant and rooted is known as a clone.
Cobalt is a micronutrient, that is a catalyst in nitrogen fixation and also essential to plant health as it is necessary for beneficial bacteria to grow and flourish. Deficient levels could result in nitrogen deficiency symptoms.
CONDUCTIVITY FACTOR (CF)
A method for checking the strength of a nutrient solution is to measure how well it conducts electricity. As nutrients are added to the water it increases the flow of electricity, so measuring the conductivity factor (CF) in a solution with a meter gives a direct indication of the strength of nutrients in a solution.
A contactor is used to control the electrical loads used to ignite and run High Intensity Discharge (HID) lights. Most contactor units will have two plugs that need connecting to a mains power supply, a box containing a relay, and sockets to plug your HID lights into. One of the contactor plugs is plugged directly into the mains power supply, and the other plug is plugged into a mechanical or digital timer and then into the mains power supply. The timer will control the on and off periods for the lights and the contactor will safely control the load that passes through to the ballast and lamp, allowing frequent on off cycles without lamp failure.
Copper is a micronutrient, which is a component of some enzymes and of vitamin A. It is required in photosynthesis, respiration and in carbohydrate and nitrogen metabolism. A copper deficiency affects plants more in the fruit and seed formation, than in vegetative growth. Copper may become toxic to plants at high levels.
A cutting is a section of plant (stem, leaves) that is removed from a donor plant at the growing tip of a branch, and placed into water or a moist growing medium for roots to develop.
Cytokinins are plant hormones that promote cell division and are primarily involved in cell growth. Cytokinins are used to help the plant make more efficient use of existing nutrients and water, and delay the ageing of leaves