Lighting For Indoor Plant Growth
Growell – http://www.growell.co.uk
Indoor gardening is a rewarding hobby that can keep you supplied with your favourite fruit and veg all year round, but your choice of grow light can make a significant difference to the overall yield and quality of your crop.
There are many different types of light system and lamp that can be used to grow plants indoors, and the choice that you make needs to be carefully considered and measured against the size and type of plants you want to grow.
The first thing that you need to understand is that plants use different parts of the light spectrum depending upon which stage of growth they are in. Young plants or plants growing in the vegetative growth stage (before any fruits or flowers form) need light primarily in the blue spectrum. This is because in nature, when plants are at this stage it is usually springtime, the sun is still quite low in the sky and the natural light is very cool in spectrum.
Once plants begin to form fruits and flowers they need light from the red/orange spectrum. This again is to mimic nature as these stage in plant development usually occur well into summer where the sun is high in the sky and the light is warm in spectrum.
In practical terms it is often best to choose an all-round light that can cater for all growth stages, but for the best results you may wish to consider different lamp types for different stages of growth.
As well as spectrum, you also need to consider light type and the intensity of light that is required. For young plants (that require blue light) there are many fluorescent lighting systems that are suitable, but these lights may struggle once the plants become larger in size. That said though, if you are growing something relatively small such as lettuce, then a fluorescent light would be ideal.
If you want to grow plants that become larger and have more dense foliage then a more powerful light source will be required to give sufficient canopy penetration. High Intensity Discharge lights are used in most commercial greenhouses around the world, and these systems can also be used on a smaller scale in indoor growing. These are typically available to power two types of lamp, metal halide lamps (for blue spectrum light) and sodium lamps (for orange spectrum light). These are available in varying degrees of power from small 250 Watt Systems to extremely powerful 1000 Watt Systems.
The latest development in plant lighting is in the form of LED lighting. Still at the research and development stage, early testing shows deficiencies in spectrum, but with technology rapidly evolveing, these lights are probable the next generation in waiting once the designs have been refined.
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December 2nd, 2011 - 11:00 pm
Hydroponics shop, UK delivery. Everything you need to get growing, with hydroponics supplies like systems, kits, lights and tents.