Grow lights
Hydroponics can be a means of growing plants in nutrient water without using soil. Instead of soil a non-reacting medium is employed such as perlite, gravel, or husk of coconuts. It was known as early as the 18 century that plants absorb their minerals in water as ions. The soil in traditional growing acts as a nutrient reservoir but won't actually contribute to plants growth. Water dissolves the minerals inside the plants soil enabling the plants to use them. In hydroponics the minerals essential for plants growth are artificially dissolved in water making soil unnecessary. It's possible to grow almost any soil based plant using hydroponics. Hydroponics is really a promising field there's much research into various methods in the academic community.
The first book ever published on hydroponics was published in 1627. Then, water cultivation soon was a popular technique. Experiments were done along with 1699 it was found that plants grown in distilled water grew less rapidly then plants grown in plain water. This can be due to the dissolved ions found within non-pure water. By 1842 scientists had published a summary of nine elements considered to be responsible for plant growth and the results of which generated what is known as modern hydroponics. Initially they used soilless cultivation and grew terrestrial plants while using the nine essential elements. It quickly spread all through academia and became an area of hot research.
One of the primary achievements of hydroponics was performed by Dr. Gericke at the University of Berkley. He was able to create tomato plants that grew to in excess of 25 feet tall. At that time this was considered only possible due to the usage of hydroponics. He claimed that hydroponics would revolutionize growing. If perhaps he were alive right now to see how it has. He wrote a book in 1940 called the Complete Help guide to Soilless Growing which took over as go to guide on hydroponics of the day; although, at first he refused to publicly reveal his secret.
As a result of extravagant nature of his claims several scientists go about reviewing his work. To start with they found that soilless growing wasn't any better than soil growing. They discovered that the yield of crops were restricted by other factors other than minerals, including light. The research overlooked most of the important factors that make hydroponics benefit plants. Namely that hydroponics allows the plants roots to seize more oxygen. During this time period mineral solutions were developed called Hoagland solutions were developed and still in use today. Hydroponics was adopted on Wake Island ahead of time to grow vegetables high was no soil. Recently hydroponics may be thoroughly researched by NASA.
With all the advancement of modern hydroponics along came advances in grow lights. To start with the introduction of HPS (high pressure sodium) grow lights allowed plants to be grown indoors. They produced high light output and allowed plants to mature fully. Recently the advances of LED grow lights initiated a policy of to revolutionize the industry of hydroponics. They completely remove the heat issues that come about with HPS lights which enable it to reduce electrical costs by up to two thirds.