36 



THE CANADIAN HORTICULTURIST 



February, 191 1 



Tomato GroMring Under Glass"" 



Prof. W. S. Blair, Macdonald College, Que. 



THE growing of tomatoes under 

 glass or "Forcing tomatoes," as 

 it is termed, has been carried on in 

 an experimental way on a commercial 

 basis during the past four years at Mac- 

 donald College. The object is to secure 

 information as to its value as a com- 

 mercial greenhouse crop. 



The seed is started in flats. As soon 

 as the true leaf appears, or in about three 

 weeks' time, the plants are transplanted 

 into other flats, spacing the plants three 

 by three inches apart. Here they remain 

 for another two or three weeks, when 

 they are potted into three and one-half 

 inch pots, where they remain until plant- 

 ed into permanent quarters. The plants 

 as a general rule may be carried in the 

 pots for three to four weeks. The plants 

 should not remain in these pots too long 

 or they will become pot-bound and get 

 stunted. If it is necessary to carry the 

 plants longer before benching it is ad- 

 visable to shift them into a larger pot. 



It requires from four to five months 

 to bring a forced tomato plant into bear- 

 ing. Seed started the first of July will 

 give good plants for benching in six 

 weeks' time, whereas seed started the 

 first of November will give equally good 

 plants only in ten weeks' time. It re- 

 quires a month longer to develop a plant 

 during winter for benching. 



One house was planted with Living- 

 ston Globe tomatoes grown as follows : 

 Seed sown July 4th, transplanted to flats 

 July 15, potted into three and one-half 

 inch pots August ist, planted permanent- 

 ly August 24th, first ripe fruit harvested 

 November nth. 



The plants were set 18 inches by 18 

 inches apart, with a space of two and 

 one-half feet apart between every fourth 

 row running lengthwise of the house. 

 The yield was 1.65 lbs. per square foot 

 of bench soil. The tomatoes netted 

 twenty cents per pound, giving thirty- 

 three cents per square foot of bench soil 

 occupied by the plants. The same bench 

 was planted January 19th from seed 

 sown November 6th. Transplanted into 

 flats November 26th, transplanted into 

 three and one-half inch pots December 

 rsth, and benched January 19th. The 

 first fruit was picked April 27th, and the 

 last was picked June 21st. The plants 

 were spaced. 18 inches by 18 inches apart 

 similar to the early planting. The yield 

 per square foot was 1.42 lbs., which 

 netted eighteen cents per pound, or 25.56 

 cents per square foot of bench area. This 

 gave a total of 58.56 cents per square 



* Extract from a paper rea4 at the recent 

 second annual convention of the Province of 

 Quebec Vesetal)le Qrowera' Association. Fur- 

 ther information about these experiments was 

 published in the Canadian Horticulturist for 

 August, 1910. 



foot of bench area from July 4th, 1909, 

 to June 2ist, 1910. 



One house from seed .sown November 

 9th, transplanted into flats November 

 30th, potted into three and one-half inch 

 pots December 29th, and planted Febru- 

 ary 1st, produced ripe fruit .April loth. 

 The plants were spaced fifteen inches 

 apart and produced four pounds per 

 plant, equal to 3.1 pounds per square 

 foot, which at fifteen cents per pound 

 would equal forty-six and one-half cents 

 per square foot for bench space from 

 February ist to end of season. 



WHEN TO START THE SEED 



Experiments conducted at various 

 times would seem to indicate that the 

 seed for a profitable fall crop should be 

 started the first of July and for the spring 

 crop the latter part of October or early 

 in November. It would seem necessary 

 to get the fruit well set by the middle of 

 November for the fall crop for after that 

 date with the short days it is extremely 

 difficult to secure a satisfactory blos.som 

 cluster and the flowers do not set fruit 

 well even if carefully pollinated. 



Plants started early in November 

 should be ready to bench early in Janu- 

 ary as soon as the July started crop is 

 finished. In this way two crops are taken 

 from the bench in one season. The yields 

 shown here are not as large as may be 

 expected, under average greenhouse 

 conditions for the reason that various 

 tests were being conducted, and the 

 yields are an average of the yield from 

 different plots. Four pounds per square 

 foot of bench area can be safely figured 

 on for the sea.son. In very few ca.ses 

 have we gone below that yield. The 

 yield will vary from three to five pounds 

 per plant according to the season. Green- 

 house tomatoes can be easily disposed of 

 at fifteen cents per pound for the season, 

 which would net the growers sixty cents 

 per square foot. 



The cost of heating is much greater 

 than for lettuce. The houses have to 

 be maintained at a temperature of about 

 sixty to sixty-two degrees at night and 

 ten degrees higher during dull days. 



SINGLE STEM SYSTEM 



Tomatoes are usually trained to a 

 single stem. This represents consider- 

 able work, as all lateral growths have to 

 be pinched ofi^ as they start out at the 

 base of the leaves. If it is desired to 

 train to two stems one of the first lateral 

 branches are allowed to grow and it is 

 treated the same as the other branch, all 

 lateral growth being removed as it 

 forms. As already stated, 18 inches by 

 18 inches apart .seems to be a satisfac- 

 tory distance, providing a two and one- 

 half foot space tuns lengthwise of the 

 hoiise between everv fourth and fifth 



row. Rows two feet apart east and west 

 and eighteen inches north and south 

 .serve well in a greenhouse where no such 

 space is given. 



The plants must be supported. For 

 this purpose horizontal wires may be run 

 along lengthwi.se of the house at the bast- 

 of the plant and another placed directly 

 over this six feet or seven feet higher. 

 Between these, strong cord such as bind- 

 er twine, may be run perpendicular, one 

 string to each plant and the plant tied to 

 it with raflTia. Care should be taken to 

 wrap raffia once around the string to 

 prevent slipping and place it under the 

 leaf so as to support the plant as well 

 when carrying a weight of fruit. No. 10 

 galvanized wire may be used in place of 

 string, and it is much better, but the first 

 cost is greater. These seven and one- 

 half feet long cost about one and one-half 

 cents each. It is necessary to have small 

 wire along the top to support these wires, 

 one end being stuck in the ground by the 

 plant and the other fastened to the upper 

 wire. For the smaller upper support 

 wires No. 18 galvanized wire is best. 



If attention is given to the pollination 

 of the tomato there will be a much less 

 number of small, medium-sized and 

 rough tomatoes. The most satisfactorv 

 way with us is to fasten a rabbit's tail 

 to the end of a stick and brush the plants 

 with it, going from flower to flower. The 

 pollen catches on the fine hair, and if the 

 brush is kept clean by occasional wash- 

 ing good work can be done. 



THE POLLEN 



Should there be a succession of sunnv 

 days and during approaching spring the 

 pollen may distribute sufficiently by tap- 

 ping the vine with a padded stick or 

 shaking the plant. The pollen is dis- 

 charged most freely in a hot, dry atmo- 

 sphere, therefore, to keep the house at 

 a high temperature during the day favors 

 the bursting of the pollen sacks even in 

 cloudy wather. The best time for pollin- 

 ating is between eleven and twelve 

 o'clock. The pollen is not discharged 

 from the anthers until after the yellow 

 petals have fully expanded and commenc- 

 ed to wither slightly. When pollen falls 

 upon one side of the stigma a one-sided 

 tomato results. The amount of pollen 

 supplied to the stigma within certain 

 limits determines to a very great extent 

 the size and smoothness of the tomato. 



Tomatoes will not do at a low temper- 

 ature. Satisfactory plants cannot be 

 grown in a lettuce house temperature. If 

 plants are to be started some provision 

 must be made for this part of the house 

 to run at 60 degrees at least. 



High, warm, sandy soil and nearness 

 to a large body of water to prevent late 

 spring frosts, is necessary to grow to- 

 matoes and cucumbers for the early mar- 

 ket. — W. W. Hilborn, Leamington, Ont. 



