This section is from the book "Commercial Gardening Vol4", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
In the Channel Islands (Guernsey and Jersey) Tomato growing for market is practised extensively. In Guernsey the plants are grown chiefly under glass, but in Jersey they are mostly grown in the open air. The climate is milder than in most parts of England or Scotland, but is no more favourable for Tomato growing in the open air than parts of Devonshire and Cornwall and the south and west of Ireland. Indeed it is a question if the mildness and humidity of the Channel Islands are not drawbacks instead of advantages to the cultivation of Tomatoes. Whether grown under glass in Guernsey, or in the open air in Jersey, the plants seem to fall an easy prey to fungoid diseases, and it is not unusual to see thousands of plants in Jersey simply putrid with disease, although they have been heavily sprayed two or three times with poisonous Bordeaux mixture.
In Guernsey Tomatoes are grown under glass in the same way as in England, either in large pots or planted out, and trained up by means of string or bamboo canes. Very little ventilation is given, most growers firmly believing that opening ventilators is equivalent to spreading the disease amongst the plants. There may be some truth in this now, as there must be millions of spores in the atmosphere as the result of bad cultivation in former years. It is nevertheless bad for the Tomatoes to plant them so close together and to keep the houses so badly ventilated as they are in Guernsey. The tissues of the plants become so tender that the spores of the various diseases germinate upon them readily and cause havoc that often cannot be suppressed or prevented with all the nostrums so loudly recommended in some quarters.
Another fruitful cause, and perhaps the main cause, of the prevalence of Tomato diseases in the Channel Islands, is the enormous quantities of chemical manures or fertilizers used by many growers. Instead of cultivating the soil deeply, and ringing the changes upon layer after layer to a good depth, the soil is drenched with some chemical manure, and when that does not produce speedy and miraculous results, another brand is tried with similar results. Hence the cost of cultivating Tomatoes in the Channel Islands is usually much greater than in English establishments. The houses are built much more strongly than in England, and much valuable light is excluded by having narrow panes of glass, and huge division rafters about 5 or 6 ft. from each other. These are said to be necessary to give the houses strength against the gales, but it is questionable whether the grower is not more or less at the mercy of the island carpenter.
In Jersey there are few glass establishments devoted to Tomatoes. The largest is that of Messrs. Bashford, at St. Saviours. In one house, 777 ft. long and 32 ft. wide (over 1/2 ac. in extent), about 12 tons of tomatoes are produced annually. From Christmas till October in one season the houses are occupied with Tomatoes. The next crop is Potatoes from October till March and April, and these are followed again by Tomatoes, with a row of Runner Beans after every third row. With such rotations as Potatoes and Tomatoes, which are practically similar in their nature, in their likes and dislikes, and in the fungoid diseases that attack them, it would not be wonderful to find the diseases left behind by one crop playing havoc with the next.
So far as the outdoor culture of Tomatoes in Jersey is concerned, plenty of space is given to the plants. The rows are usually 3 ft. apart, the plants being 15 to 18 in. apart in the rows. Each one is tied to a bamboo stake, and as a rule about three bunches of fruit are allowed to mature upon each plant. From 9000 to 10,000 plants are thus grown to the acre, although in many cases there are probably 12,000 to 13,000 plants in the same space. Allowing for disease and failures, 15,000 lb. of fruit per acre would be a fair estimate, and reckoning these at Id. per pound, the yield per acre would be something over £62 per acre, about half of which would be clear profit. More could certainly be realized if the soil were better and more deeply cultivated, and if the weeds were kept down by frequent hoeing. What expense is at present saved by not performing these very necessary cultural operations is more than counterbalanced by the cost of the Bordeaux mixture that is sprayed so lavishly over the crops, making the plants unsightly and the fruits at least risky to consumers. [J. W].
Tomatoes must be considered as a special crop in and around the Vale of Evesham, where they are grown in the open air and without shelter of any kind except what may be derived from the adjacent fruit trees. The market gardeners commenced to give this crop their attention rather more than twenty years ago, since when it has extended to 250 or 300 ac. In 1908 one man alone grew about 30 ac. of Tomatoes - a risk which some men would not care to take. They go to supply the English, Welsh, and Scottish markets with cheap tomatoes during the months of September and October especially; and if the grower can obtain a net price of five, six, or seven farthings per pound he is amply repaid by a good crop. "Glass" is conspicuous by its absence from such an important commercial horticultural centre, the only place possessing any appreciable quantity being the "French Garden", owned by Mr. J. N. Harvey.
The few gardeners who have one or two small and warm greenhouses supply their neighbours with young Tomato plants at a cheap rate per thousand during the latter half of May. These are planted usually in the warmest positions available, in rows about 4 ft. apart and 30 in. or 3 ft. apart in the rows, and tied and trained to a stick or small bamboo cane left about 3 ft. above the ground. As previously stated, one man has grown 30 ac. of Tomatoes; but usually the area devoted to them by individual growers varies from 1/2 ac. to 4 ac.
Considerable attention is paid to this crop in the matter of watering, tying, and pinching out the side shoots during the chief period of growth; and in August and September a part of the foliage is removed for the purpose of hastening the ripening of the fruit. An important item in the details of cultivation of this crop in the open ground is to have sturdy plants at, or very near, the fruiting condition at the time of planting at the end of May or very early in June. If a bunch of fruit be "set" on each plant at this time, failure is as far removed as it can possibly be under this system. [J. U].