Stresses are caused to your plants whenever an imbalance occurs within the plant chemistry. The normal chemical reactions and interactions within the plant are disrupted and an ageing hormone called Ethylene is produced in the cells.
Plants like to have regular days without any surprises. Any event which detracts from this ideal norm will cause changes to the plant’s internal chemistry. Such changes will result in the plant becoming stressed and a subsequent reduction in growth occurring.
What are the Main Factors Which Stress My Plants?
Too much or too little water for the plant’s needs causes a hormone (abscisic acid) to build up in the leaves. This hormone shuts down the stomata stopping transpiration and gaseous exchange occurring.
A surplus or deficit of nutrient, or an imbalance within that nutrient solution, can leave the plant open to attack by disease or from Nematodes. These slender parasitic worms will cause disruption to the normal functioning of the plant’s root system.
An imbalance of minerals within the plant will cause stress to it. The most common cause of this is bad nutrient management. Systems, often those where the run-off is reused, which are not monitored accurately can cause all kinds of imbalances within the plant chemistry.. The resulting slowing in growth rate is rarely noticed for some time. By the time the damage is discovered the problem is often quite advanced and will usually take at least a week to recovery.
The chemical changes which take place within the nutrient, as the plant uses up the chemicals it needs at that time, alter the pH of the remaining nutrient available to the plant. As the plant transpires and loses water from its leaves the pH will also alter. These changes need to be minimised to allow the plant to maximise its uptake of nutrients, (The chemical imbalance means that the plant has to work harder to obtain less nutrition.)
As the plant becomes older it requires less in the way of nutrients. An analysis of its tissues will show that the amounts of the various minerals used have altered a great deal. To get the best results, your plant needs to be monitored daily and the nutrients supplied altered each week to match its requirements.
The intensity and duration of the light supplied to the plant must be monitored in order to simulate the daytime/night time ratio for the plant’s optimum habitat. This is especially important in plants that use the length of light or dark to determine when to flower.
Physical injury to the plant will cause it to alter its internal chemistry in order to effect repairs. Root damage; be it physical or chemical, will result in that section of the root being sealed off. Roots do not regenerate and the plant must have new root tips with fully functioning root hairs in order to absorb water, so it will just alter it’s internal chemistry to enable increased root production and grow around the damage.
All kinds of diseases can impair you plant’s growth. Any viral or bacterial invasion will activate its defence mechanisms. This in turn will cause internal changes to the plant chemistry resulting in stress.
Extremes of weather in the natural world cause lots of changes within plants. For example a severe drought will cause trees to shut down early and ‘winter’ longer until the water is more readily available. This is seen in the tree rings and tells scientists what the climate did during years past.
Another common result is early seeding, often producing a crop of all female seeds each of which is a clone of its parent. This is due to the absence of a male flower with mature pollen at the time of fertilisation.
This viable seed production is nature’s way of ensuring the species survives. It is a good idea to ensure that your hydroponically grown plants do not suffer from this problem as the yield will be severely compromised.
What Can Be Done To Restore Health To A Stressed Plant?
The plant has a natural remedy for stress. It produces Thiamine, commonly known as Vitamin B1, which acts as a catalyst and helps restore the chemical balance within the plant. It is usual to treat plants under stress with a proprietary formula containing Thiamine as well as some other helpful chemicals. Some preparations include Vitamin B6 and nicotinic acid, which are thought to stimulate growth, whilst others add many other vitamins which are said to benefit the plant in various ways.