Patent GB-355655-A (GB)
Title: Improvements in or relating to pots and other receptacles suitable for growing plants
IPC: A01G9/10
Filed: 1930-04-17
Abstract: A plant pot is made of base material of a calcareous or of both calcareous and aluminous nature, and plant food, and is, wholly or partly, extending from its inner side, of a cellular character obtained by generation of gas in, or by blowing air through the material while it is in a wet condition.  In order to generate gas, substances which do this when wet may be added, such as aluminium powder with or without sodium hyposulphite, or yeast and flour.  The base material may comprise fibrous material such as vegetable fibre, or consist of asbestos cement, or potting fibre, or chopped straw, or both, and Portland cement, or asbestos cement, vegetable fibre and Portland cement.  The cement should be as little caustic as possible. Old Portland cement, or waste asbestos cement from the manufacture of roofing sheets or pipes may be used.  The plant food may consist of basic slag, an alkali salt, such as sodium nitrate, an ammonia salt, animal manure, or a mixture of two or more of such substances.  The pot may be provided with a lining of the composite material containing gas generating material.  The plant food may be disseminated through the wall of the pot, as by immersion in a solution.  The pots may be reinforced by wire wound round while they are moist.  Sheet material for making the pots may be prepared by taking a sheet of moist base material, applying plant food and gas generating material to one side, rolling into the form of a hollow cylinder, and slitting longitudinally.  The pots are allowed to dry and assume a cellular condition in a warm atmosphere.  Or the base material may be made into a slurry with water and fed on to an endless web passing over a suction box.  When stripped from the web it is wound on a rotating cylinder to form a number of convolutions. Pots are made from the cylinder as before.  Each pot is provided with a lining of composite material.  The plant food may be added while the base material is on the web.  The lining may alternatively be formed by inserting a lump of soft composite material at the bottom of a dry pot and forcing it around the inner wall with a former.  The lining is then allowed to dry slowly.  Specification 355,278 is referred to.  According to the Provisional Specification the base material may consist of agricultural lime.ALSO:A plant pot is made of base material of a calcareous, or of both a calcareous and aluminous nature, and plant food, and is, wholly or partly, of a cellular character obtained by generation of gas in, or by blowing air through the material while it is in a wet condition.  In order to generate gas, substances which do this when wet may be added, such as aluminium powder with or without sodium hyposulphite, or yeast and flour.  The base material may comprise fibrous material such as vegetable fibre, or consist of asbestos cement, or potting fibre, or chopped straw, or both, and Portland cement, or asbestos cement, vegetable fibre and p  Portland cement.  The cement should be as little caustic as possible.  Old Portland cement, or waste asbestos cement from the manufacture of roofing sheets or pipes may be used. The plant food may consist of basic slag, an alkali salt, such as sodium nitrate, an ammonia salt, animal manure, or a mixture of two or more of such substances.  The pot may be provided with a lining of the composite material containing gas generating material. Specification 355,278 is referred to.  According to the Provisional Specification the base material may consist of agricultural lime.