Irving D: A guide to growing Marijuana in the British Isles and other cool climates. UK 1978 - 48pp - republished 1995 as "A guide to growing Marijuana in cool climates" - 47pp

The original (or at least the copy in my possession) carries no disclaimer, the introduction stating "In producing this book we don't wish to repeat lengthy argument for and against the legalisation of cannabis. Anyone merely glancing at this book will be well familiar with the outrageous hypocrisy of successive authorities' attitude to marijuana and all other hallucinogens".

Disclaimer: Contained in the 1995 version: "Warning - It is a criminal offence in the United Kingdom, punishable by imprisonment, to cultivate, possess or supply Cannabis. You should therefore understand that this book is intended for private amusement, and not intended to encourage you to break the law.

This booklet has been available in the UK for the past 17 years, and has recently been republished with colour photographs and amendments to the text. As the guide has been available in the UK for some time, I shall refer to the original version unless otherwise stated.

The booklet starts with a historical introduction, followed by a discussion of the botany, a description of the plant and the main sex differences. The 1995 version updates the botanical knowledge, current taxonomic conventions, and a more detailed account of cannabinoid phenotypes.

The effect of latitude and climate for outdoor growers is discussed with a map showing expected dates of first and last frosts in different parts of the UK. The author gives advice on choosing a site (advises south-facing slopes), and the 1995 version advises when to plant (late March).

Both versions contain identical sections on soil preparation, favouring an organic approach, and advising on the soil quality, texture, pH value and nutrient content, with advice on how to produce compost from domestic waste, as well as the value of earthworms.

There are differences in the advice on seed selection between the two versions, the author now suggesting that seeds from potent original plants should be sought, rather than those which have acclimatised to UK conditions. Both versions give the same advice on planting (in shallow soil), transplanting and hardening-off, with the new version giving a section on propagation.

The sections on plant care advise on feeding (nitrogen for growth, potassium/phosphate for flowering) soil deficiency, pruning, cuttings (new version as propagation above), stem manipulation and pests (new version discusses stress and stressing practices).

Chapter on the perfect environment discusses light (natural) photosynthesis, photoperiodism, temperature, water. and modifying the outdoor environment, with diagrams of male and female plants, and of using water barrels to store heat in a lean-to greenhouse.

Chapter on maturity discusses identification of pubescent flowers, the dilemma between sinsemilla and seed production, removing males to produce sinsemilla, and the incidence of hermaphrodite plants. Diagrams of immature and mature flowers.

Chapter on harvesting, denotes the critical balance between keeping plants outdoors for optimum flower production, or harvesting them before they are destroyed by frost. Discussion of grading, drying, curing and storage.

 

Chapter on indoor growing: Original booklet refers to hydroponics as experimental technology. The latest version deals in much more detail with hydroponic cultivation. Original booklet recommends "gro-lux" fluorescent tubes for indoor cultivation, with output spectrum chart of standard and gro-lux tubes. New version describes high-intensity discharge lights, specifically mentioning with approval: mercury tungsten filament, mercury vapour, metal halide and high-pressure sodium lights. New version omits chart and diagram showing growroom under fluorescent lights. Both versions discuss day length for vegetative growth and flowering, newer version suggesting 18 hours vegetative, and 12 hours for flowering (original version 16-18hrs and under 13 hrs respectively). References in original version to fluorescent lights are omitted from the section on "indoor set-ups" the author now recommending cultivation of many smaller plants, rather than fewer large plants, in a restricted space. Newer version gives more detail on indoor environment with sections on proper ventilation, heating, and maintenance of watering in hydroponic systems.

Chapter on advanced techniques discusses selective breeding, production of female seeds (from hermaphrodite plants), cross-breeding techniques, use of colchicine (now not discussed with the same enthusiasm as 1978) and provision of additional CO2.

Contains bibliography, new version contains advertisement for Magic Mushroom guide.

Comment: This is the classic UK text, in original or amended form. It involves simple step-by-step instructions for growing cannabis, mainly outdoors, from seed to harvest. The original carried no disclaimer, and I understand that this booklet was the subject of a previous prosecution (R-v-Toskanex 1985) where the publisher was acquitted on obscenity charges. The recent revision brings the publication up to date, with about 10 to 20% of the booklet being revised or re-written. In particular, the use of gro-lux fluorescent tubes has been eclipsed by high-powered growlights supplied by specialist retailers.