Employ a deeper container filled with moist peat. Plants do particularly well in such containers if the pot is plunged to the rim in the peat. The individual requirements of each plant can then be checked.

There are many beautiful dieffenbachias available, the majority of which are a little difficult to care for; Jenbuchia Pia can be among the most troublesome. The main difficulty is that the leaves contain very little chlorophyll, being almost entirely creamy white in colour.

Grouped together plants create a certain amount of humidity and feeling around one another, and this is a very important requirement in hot and dry room conditions. In the greenhouse we can combat the dry atmosphere created by the heating pipes by frequent damping of the area around the plants, and by wetting the ground beneath the staging and the pathways as frequently as possible.

This damping down operation may take place several times daily, vet it may not be necessary to water the compost in which the plants are actually growing. If the compost is watered each time the greenhouse is damped down the soil will become totally saturated, depriving the roots of oxygen, a condition which few plants can tolerate for long.

As well as the National Dahlia Society, which caters for both amateur and professional growers alike, there is a trade organisation known as the British Dahlia Growers Association.

Modern varieties, without doubt, are really wonderful, both in formation and in the period and length of blooming. The majority of giant varieties have originated overseas, although we have several raisers of these varieties within the confines of the British Isles, notably that doyen of the dahlia, Mr Harry Stredwick, whose giants are famous the world over.

Australia and America in particular have produced some really wonderful varieties which are to be seen in every keen grower’s garden. The medium and small varieties, up to a few years ago, were, in the main, of native origin, but of late years we have seen a gradual influx of varieties from other countries. Holland, in particular, is responsible for a really wonderful range of medium cactus which have literally revolutionised this very attractive section. But France, Germany, South Africa, Australia and the Iron Curtain countries, plus a whole host of other nations, have all sent varieties which are grown enthusiastically, so that it is perhaps invidious to even imply that any country excels in this particular phase.

The quills, which may be incompletely dried, may be recleaned, washed in fresh water, thoroughly dried and packed. Good Chinese cassia bark is sweet and aromatic, resembling Ceylon cinnamon in flavour, but is rather less delicate and sometimes slightly astringent; it is less uniformly thin and darker in colour; the outer bark is often less carefully removed, leaving patches of rough, greyish bark.

The bark is removed from the standing tree at the time when it lifts easily, starting with the main branches and working down the trunk. A bambdo scaffolding may be erected for the purpose. Horizontal cuts are made about 40 cm apart and vertical cuts some 25-35 cm apart. The rectangles of bark are then removed with the aid of a horn or bamboo spatula. Finally, the tree is felled and the inferior bark removed from the smaller branches. A stump may he left to encourage coppicing.

In comparison to cinnamon bark oil, the production of cassia bark oils is on a relatively small scale with distillation being undertaken in the importing countries. These oils find a limited use in soaps, perfumes, some spice essences and beverages.

Compound quills, measuring 42 ins. long (just over 1 m), are sorted into grades according to the thickness of the hark. Three main qualities are exported: the ‘Tine’ or ‘Continental’ grades, the intermediate `Mexican’ grades, and the ‘Hamburg’ grades.

In the USA, spice millers cut selected pieces of the three types of cassia bark into short lengths for sale as ‘whole cinnamon’. The great bulk of the cassias imported is ground to produce ‘ground cassia- cinnamon’. The various kinds of cassia bark are different in flavour and degree of aroma, but all are agreeable, fragrant and aromatic. Saigon cassia is generally acknowledged to possess the fullest and finest flavour and it is the preferred type in the USA. The various types are ground separately or blended to meet the needs of the bakery and food- processing industries, being used directly in the ground form or for oleoresin extraction. Ground cassias are sold for domestic culinary use, usually without distinction as to type, under the label of ‘cassia- cinnamon’.

Cinnamon may be propagated by seeds or vegetatively. As the fruits are avidly eaten by birds, it is usually necessary to bag the fruits to protect them from depredation. The fruits are usually kept in heaps pulp rots; the seeds are then washed and dried in the shade. The seeds should be planted as soon as possible as viability is quickly reduced. Kannan and Balakrishnan n India sowed freshly harvested seed daily for the first seven days and weekly for seven weeks thereafter. The highest rate of germination of 94 per cent was obtained by sowing the third day after the seeds were harvested.

By the end of the second week after harvesting the germination was reduced to 52 per cent; after 40 days of storage there was a complete loss of viability. Seeds sown during the first week germinated within 20-25 days; afterwards 32-42 days were required for germination. The seeds may be sown in nurseries or at stake in the field.

Several cultivars with distinctive local names exist in Sri Lanka. The forms recognized by growers include sweet or honey cinnamon, snake cinnamon, camphor cinnamon, astringent cinnamon, mucilaginous cinnamon, wild cinnamon and bloom cinnamon. Their characteristics are not given, but of these only sweet or honey cinnamon is cultivated extensively.

Cinnamon bark oil is a pale-yellow liquid possessing the delicate aroma of the spice and a sweet and pungent taste. Its major constituent is cinnamaldehyde, but other components present in minor or trace quantities impart the characteristic odour and flavour which distinguishes this oil from other Cinnamomum bark oils. These components include eugenol, eugenol acetate and small amounts of aldehydes, ketones, alcohols, esters and terpenes. Arctander (1960) attributes the powerful characteristic notes of good oils to the presence of methyl-namylketone together with other, aldehydes and ketones. However, detailed studies of the relationship of the oil composition to its organoleptic properties have not been reported in the literature.

The yield and quality of cinnamon bark oil are highly dependent upon a number of factors which have been mentioned above and in the `Processing and manufacture’ section. In addition, environmental factors such as soil, climate and altitude appear to be as important as any evolved varietal differences on the quality of hark oils obtained from C.verum grown in different countries.

In comparison to Sri Lankan bark oil, the Seychelles product was found to he poorer in odour and flavour and less soluble in alcohol, and it was not possible to produce a Seychelles cinnamon bark oil which could satisfy the requirements of the British Pharmacopoeia.

Chinese cassia is cultivated mainly in the provinces of Kwangsi and Kwangtung in southern China. It was once harvested from wild bushes growing in the mountains in addition to cultivated bushes, but is now restricted to the latter.

They should, however, be planted close enough to encourage the formation of a tall straight trunk with as few branches as possible. The best spacing is about 1 m between plants. The use of Tephrosia candida (Roxb.) DC. as a nurse crop has been recommended in Sumatra. This may be sown six months ahead of the cassia in rows about 1 m apart and the young cassia trees are planted in clearings about 60-70 cm in diameter made in the Tephrosia, which later can be cut back to 15 cm and spread between the rows.

Chinese cassia is mentioned in the Elegies of Ch’u written in the fourth century B.C. Laufer says that the first Chinese description of it was written in the third century, and that the medicinal use of the bark was first mentioned by T’ao Hun-kin (A.D. 451-536). However, that knowledge of it would be much older’.

Heating by means of oil heaters is comparatively widely practised, and in a small greenhouse there is a lot to be said in favour of this method. There are however a number of disadvantages. If a high temperature is maintained the cost, although much less than electrical heating, is higher per cubic foot of space than the boiler system. Then too this form of heating, as it relies upon a supply of oxygen for combustion, has a very serious drying effect on the air; this can be minimised by using water trays, but it is not easy to maintain a buoyant atmosphere even when these are used.

Even if a greenhouse is not available it is still possible to propa:sate successfully by using a heated frame. This method has disadvantages, the chief being the discomfort to the grower: the plants will be covered during inclement weather, but he will not. The rate of growth will also be slower.

Nero is said to have burned cinnamon in Rome at his wife’s funeral included five pounds of cinnamon in a list of spices supplied to a monastery in Normandy in A.D. 716.

The spice is used in baking and pickling; it has also a limited use in pharmaceutical products and in incense. Like many other spices, cinnamon was regarded as having aphrodisiac properties.

Cinnamon bark oil is obtained by steam distillation of the bark and is used in flavouring and perfumery. Cinnamon leaf oil is obtained by steam distillation of the leaves; its composition is different from that of the bark oil and it is a source of eugenol; it is also used as a flavouring and in perfumery.

Cassia, which is usually considered as somewhat inferior to true cinnamon, is of different kinds obtained from different species of Cinnamotnurn. These include: Chinese cassia from C. cassia, which is cultivated in south-eastern China; Indonesian cassia from C. burmannii, which occurs wild in parts of South East Asia and is cultivated in the uplands of Padang in Sumatra; Saigon cassia, obtained principally from C. loureirii, which occurs wild and is also cultivated in Vietnam. C. cassia bark and leaf oils are obtained by steam distillation, but, unlike the cinnamon oils, have similar chemical compositions.

The Destroying Angel (Amanita virosa) is another poisonous mushroom, although quite a rare species, which is distinguished from the other type of Death Cap (A. phalloides ssp. yam) by its sharp club-shaped cap and frayed stipe. It grows predominantly in mountain forests on a limestone subsoil. It is as potentially dangerous as the Death Cap and its fruit-bodies contain another type of toxin called virosin, whose toxic effects can be compared with those of amanitoxins. It should also be mentioned that amanitoxins are present in some other fungi, which are not necessarily related to the Amanita genus. These poisonous substances were in clusters on rotten wood. It can quite easily be mistaken for the edible mushroom Kuehneromyces mutabilis.

The stipe also has a ring and the gills are permanently white. Their fruit-bodies as well as the spores contain at least 10 poisonous substances which include phalloidin and amanitoxin.

Agaric has a stupefying effect and in some countries it is used as a narcotic. It resembles the deistic potion known as Soma, which dates back. more than 3,000 years. It is also the same hallucinogenic drug: which was used long ago in Siberia, Kamchatka and Chukotka.’ by the indigenous population.