Modern Potting Composts

The last two decades have seen rapid advances in the technology used to produce pot plants. Glasshouses designed and orientated to give maximum light transmission, fully automatic heating and ventilating systems, carbon dioxide enrichment of the atmosphere, controlled photoperiods using automatic blackouts and incandescent lamps which enable plants such as chrysanthemum to be flowered at any time of the year, mist propagation techniques, chemical growth regulators which control the height of plants, automatic watering and feeding systems, etc.: these are only some of the developments which have transformed pot plant culture. There have also been many changes in the composts and systems used to grow the plants. Mineral soils, which formed the basis of the John Innes Composts, are now either too expensive or too difficult to obtain in suitable quality and sufficient quantity. Consequently the grower has been forced to seek other materials such as peat, perlite, vermiculite, plastic foam, shredded bark, etc. New types of fertilisers, new methods of heat sterilisation and new chemical sterilising agents are also being used.

Klappentext

The materials used in the preparation of composts for pot plants are changing rapidly. This book explains their nature and use as part of a range of new growing systems. Mineral soils, which formed the basis of the John Innes type of compost, are increasingly scarce and expensive, and growers are having to deal with radically different materials such as plastic foam and shredded bark. Together with improved technology, these represent new systems of growing, and not simply changes of compost.The new materials give results which are equal or even superior to those obtained by traditional means, providing their individual characteristics and requirements are understood. They are likely to be used with new types of fertilizers, new methods of heat sterilization and chemical sterilizing agents. They are part of systems which rely increasingly on a technology of growing that has been subject to extensive change and development during the past two decades--glasshouses designed to give maximum light transmission, automatic heating and ventilating systems, carbon dioxide enrichment of the atmosphere, controlled photo periods enabling certain plants to flower at any time of the year, mist propagation techniques, chemical growth regulators, automatic watering and feeding systems... and these are only part of the story.Much of the information is based on previously unpublished studies made by the author at the Glasshouse Crops Research Institute. He also draws on his experience at the John Innes Institute and on the results of experimental work carried out in many countries, in particular the U.S.A., The Netherlands, Scandinavia, and West Germany.The book is written for the professional horticulturist, and a pre-publication review suggests that it is likely to be regarded as "the nurseryman's Bible and the research and experimental worker's source book." It is the only authoritative, up to date, book-length treatment of the subject in English.

Inhalt
1 Why Change?.- 1.1 Loam composts.- 1.2 Loamless composts.- 2 Alternative Materials.- 2.1 Peat.- 2.2 Other organic materials.- 2.3 Mineral materials.- 2.4 Plastics.- 3 Physical Aspects.- 3.1 Physical terminology.- 3.2 Physical requirements of composts.- 3.3 Energy concept of water in composts.- 3.4 Water absorption and release by composts.- 3.5 Formulation of composts: physical principles.- 4 Principles of Nutrition.- 4.1 Cation exchange capacity.- 4.2 Anion exchange capacity.- 4.3 Availability of nutrients: loam v. loamless composts.- 4.4 Nutrient uptake by the plant.- 4.5 Acidity (pH).- 4.6 Lime requirement.- 4.7 Soluble salts.- 5 Nitrogen.- 5.1 Nitrogen and pot plants.- 5.2 Forms of mineral nitrogen.- 5.3 Slow release fertilisers.- 5.4 Choice of fertiliser type.- 5.5 Nitrogen and peat.- 6 Other Macro-Elements.- 6.1 Phosphorus.- 6.2 Potassium.- 6.3 Calcium.- 6.4 Magnesium.- 6.5 Sulphur.- 6.6 Mineral soil and peat comparison.- 6.7 Nutrient and environment interactions.- 6.8 Fertiliser analysis and salt index.- 6.9 Plant mineral levels.- 7 Micro-Elements.- 7.1 Boron.- 7.2 Copper.- 7.3 Manganese.- 7.4 Molybdenum.- 7.5 Iron.- 7.6 Zinc.- 7.7 Chloride.- 7.8 Aluminium.- 7.9 Fritted micro-elements.- 7.10 Chelated micro-elements.- 7.11 Other sources.- 7.12 Micro-element availability.- 8 Compost Formulation and Preparation.- 8.1 Historical.- 8.2 Denmark.- 8.3 Finland.- 8.4 Germany.- 8.5 Ireland.- 8.6 Netherlands.- 8.7 United Kingdom.- 8.8 United States of America.- 8.9 Sawdust and bark composts.- 8.10 Azalea composts.- 8.11 Proprietary formulations.- 8.12 Compost preparation.- 9 Liquid Feeding.- 9.1 Importance of liquid feeding.- 9.2 Formulating liquid feeds.- 9.3 Practical aspects of feeding.- 9.4 Diluting equipment.- 9.5 Quality of irrigation water.- 10 Irrigation Systems.- 10.1 Drip systems.- 10.2 Capillary watering.- 10.3 Flooded benches.- 11 John Innes Composts.- 11.1 Formulation.- 11.2 Compost ingredients: loam.- 11.3 Peat.- 11.4 Sand.- 11.5 Sterilisation.- 11.6 Characteristics and use.- 11.7 Composts for calcifuge plants (JIS ( A )).- 12 Heat Sterilisation.- 12.1 Thermal deathpoints.- 12.2 Methods of heat sterilisation.- 12.3 Steam.- 12.4 Steamair mixtures.- 12.5 Flame pasteuriser.- 12.6 Electrical sterilisers.- 12.7 Other methods.- 12.8 Chemistry of heat sterilisation.- 12.9 Rules for heat sterilisation.- 13 Chemical Sterilisation.- 13.1 Soil fumigants.- 13.2 Fungicides.- 13.3 Insecticides.- 14 Plant Containers.- 14.1 Clay v. plastic pots.- 14.2 Paper and peat pots.- Appendices.- 1 Metric conversions.- 2 Imperial and us capacity measures.- 3 Illumination and radiation units.- 4 Atomic weights.- 5 Formulae and molecular weights of some commonly used chemicals.- 6 Chemical gravimetric conversions.- 7 Temperature conversions.