Eric John Hewitt FRS (27 February 1919–1 January 2002) was a British plant physiologist who pioneered the study of plant nutrition in the 20th century.
He is commonly known for compiling the nutrient recipes for the Long Ashton Nutrient Solution in his landmark book on sand and water culture methods, first published in 1952 [1] and revised in 1966. [2]
Hewitt was educated at Whitgift School, graduated with a first-class BSc in botany and chemistry from King's College London, and completed his PhD at the University of Bristol in 1948. [3] Hewitt's laboratory at Long Ashton Research Station opened in 1956. He was a Reader in Plant Physiology at the University of Bristol from 1967 to 1984.
He was made a Fellow of the Royal Society in 1982. [4]
Hydroponics is a type of horticulture and a subset of hydroculture which involves growing plants, usually crops or medicinal plants, without soil, by using water-based mineral nutrient solutions. Terrestrial or aquatic plants may grow with their roots exposed to the nutritious liquid or the roots may be mechanically supported by an inert medium such as perlite, gravel, or other substrates.
The following outline is provided as an overview of and topical guide to agriculture:
Agronomy is the science and technology of producing and using plants by agriculture for food, fuel, fiber, chemicals, recreation, or land conservation. Agronomy has come to include research of plant genetics, plant physiology, meteorology, and soil science. It is the application of a combination of sciences such as biology, chemistry, economics, ecology, earth science, and genetics. Professionals of agronomy are termed agronomists.
Good agricultural practice (GAP) is a certification system for agriculture, specifying procedures that must be implemented to create food for consumers or further processing that is safe and wholesome, using sustainable methods. While there are numerous competing definitions of what methods constitute good agricultural practice, there are several broadly accepted schemes that producers can adhere too.
Horticulture is the cultivation of plants in gardens or greenhouses, as opposed to the field-scale production of crops characteristic of agriculture. It includes the cultivation of fruits, vegetables, nuts, seeds, herbs, sprouts, mushrooms, algae, flowers, seaweeds and non-food crops such as grass and ornamental trees and plants. It also includes plant conservation, landscape restoration, landscape and garden design, construction, and maintenance, and arboriculture, ornamental trees and lawns.
Julius von Sachs was a German botanist from Breslau, Prussian Silesia. He is considered the founder of experimental plant physiology and co-founder of modern water culture. Julius von Sachs and Wilhelm Knop are monumental figures in the history of botany by first demonstrating the importance of water culture for the study of plant nutrition and plant physiology in the 19th century.
Plant nutrition is the study of the chemical elements and compounds necessary for plant growth and reproduction, plant metabolism and their external supply. In its absence the plant is unable to complete a normal life cycle, or that the element is part of some essential plant constituent or metabolite. This is in accordance with Justus von Liebig’s law of the minimum. The total essential plant nutrients include seventeen different elements: carbon, oxygen and hydrogen which are absorbed from the air, whereas other nutrients including nitrogen are typically obtained from the soil.
Long Ashton Research Station (LARS) was an agricultural and horticultural government-funded research centre located in the village of Long Ashton near Bristol, UK. It was created in 1903 to study and improve the West Country cider industry and became part of the University of Bristol in 1912. Later, it expanded into fruit research and in the 1980s was redirected to work on arable crops and aspects of botany. It closed in 2003.
Aeroponics is the process of cultivating plants in an air or mist environment, eliminating the need for soil or an aggregate medium. The term "aeroponic" originates from the Greek words aer ("air") and ponos ("work"). It falls under the category of hydroponics, as water is employed in aeroponics to deliver nutrients to the plants.
Agricultural soil science is a branch of soil science that deals with the study of edaphic conditions as they relate to the production of food and fiber. In this context, it is also a constituent of the field of agronomy and is thus also described as soil agronomy.
Deep water culture (DWC) is a hydroponic method of plant production by means of suspending the plant roots in a solution of nutrient-rich, oxygenated water. Also known as deep flow technique (DFT), floating raft technology (FRT), or raceway, this method uses a rectangular tank less than one foot deep filled with a nutrient-rich solution with plants floating in Styrofoam boards on top. This method of floating the boards on the nutrient solution creates a near friction-less conveyor belt of floating rafts. DWC, along with nutrient film technique (NFT), and aggregate culture, is considered to be one of the most common hydroponic systems used today. Typically, DWC is used to grow short-term, non-fruiting crops such as leafy greens and herbs. The large volume of water helps mitigate rapid changes in temperature, pH, electrical conductivity (EC), and nutrient solution composition.
Potting soil or growing media, also known as potting mix or potting compost (UK), is a substrate used to grow plants in containers. The first recorded use of the term is from an 1861 issue of the American Agriculturist. Despite its name, little or no soil is usually used in potting soil.
Lawrence Ogilvie was a Scottish plant pathologist who pioneered the study of wheat, fruit and vegetable diseases in the 20th century.
Wilhelm Knop was a German agrochemist and co-founder of modern water culture. Alongside Julius von Sachs, he identified nitrogen, phosphorus, sulfur, potassium, calcium, magnesium, and iron as essential elements for plant nutrition. Knop and von Sachs pioneered the use of standardized nutrient solutions in experimental plant physiology.
Victor Alphons Tiedjens (1895–1975) was an American horticulturist, agronomist, biochemist and soil chemist. He was credited as "one of the pioneers in growing plants in chemical solutions."
The Hoagland solution is a hydroponic nutrient solution that was newly developed by Hoagland and Snyder in 1933, modified by Hoagland and Arnon in 1938, and revised by Arnon in 1950. It is one of the most popular artificial solution compositions for growing plants, in the scientific world at least, with more than 19,000 citations listed by Google Scholar. The Hoagland solution provides all essential elements for plant nutrition and is appropriate for supporting normal growth of a large variety of plant species.
Dennis Robert Hoagland was an American chemist and plant and soil scientist working in the fields of plant nutrition, soil chemistry, agricultural chemistry, biochemistry, and physiology. He was Professor of Plant Nutrition at the University of California at Berkeley from 1927 until his death in 1949.
Ferric EDTA is the coordination complex formed from ferric ions and EDTA. EDTA has a high affinity for ferric ions. It gives yellowish aqueous solutions.
The Kratky method is a passive hydroponic technique for growing plants suspended above a reservoir of nutrient-rich water. Because it is a non-circulating technique, no additional inputs of water or nutrients are needed after the original application, and no electricity, pumps, or water and oxygen circulation systems are required. The Kratky method has applications both for commercial food production and as a small-scale and low-maintenance technique for home growers. It has been described as "the simplest hydroponic system."
Samuel Paul Wiltshire was an English mycologist and phytopathologist. For the academic year 1943–1944 he was the president of the British Mycological Society.