[eae at Te SE oe etter Web FORCING OF LETTUCE WITH SOME EXPERIMENS Li ae EC Ae us 1898 tt sale ed tk ti el et ed eee) SE ee eT ee ae ee 4 cs Dee Swe He Oe OO Ae BG Os Le ANON) THESIS Jp ' ML ( t AL, FORCING OF LETTUCE WITH SOME EXPERIMENTS IN GROWING. BY or ee Charles W. Loomis. Class of '98, The growing of lettuce for the winter months claims no small part of the market gardener's attention and in and around our large cities may be found many who give their whole time to it. So great has become the demand for this vegetable, whose use as a relish from adds so mich to our winter diet and .’ the growing of a fow heads A in some obscure corner of the greenhouse, nowy whole acres are given to this one crop. The simplest marner of obtaining: lettuce somewhat earlier than when grown o1t of doors. is that of sowing the seel in the late fall, outside. and before frost appears the plants will have a growth of two to three inches. The young plants are now pro- tected by putting them in a frame ani covering with a ®lass sash. This does rot give sufficient warmth to enable them to continue growing, yet it protects them from injury by the cold and as soon as the warm spring days appear tiey are ready to start at once. A step higher and somewhat earlier is that of growing them in hot- beds. In the latter part of February or the first of March, @& pro- tected spot facing the south is excavated to the depth of a foot or more. This exca¥Yation is then filled with fresh horse--manure over which a layer of dirt is then placed. The whole is then enclosed in a frame and then banked up with earth and manure. Thus enough heat is given out by the manure to enable the plants to grow irrespective of the outside conditions. This rlan is very satisfactory. but the cost of erecting and caring for so many frames is considerable and as the work is accomplished at auite a disadvantage, since it must be done out of doors, bending over and at a risk of chilling the tender rlants. The best results are 102388 obtained from the forcing house, a permanent glass structure, which enables the operator to work 1nder cover at all times and to sub- stitute heating by steam or hot water, for the heat provided by the fermenting manure. The size and style of the house “epends to a large extent upon the situation of the grower as well as the amount of money he can put into it. There are several points which must be con- sidered in any house. The lettuce wants plenty of light, so care must be taken not to put too heavy sashes and woodwork above to shade the plants, also the nearer the plants are to the glass, the better they will do. Also to so arrange the interior as to have a maximum growing area with a mimimum amount of space occupied °..' by walks. There are innumerable varieties of lettuce and most growers have their own favorite strain but all come under two main classes:- the head varieties. which form a head similiar to that of a capbage and the loose or open kinds that do not head. The Boston Market. is considered the best of the head varieties while the trand Rapids Foreing holds the same place among the oren sort. The inner leaves of the head variety are very crisp and tender. The oren kinds however. can be used somewhat earlier than other kinds. In some markets tho head let*uce is unknown while in others, it is prized above all others. Whatever kind@ is used, see to it that you have good seed. It Should be saved only from plants which are ileal in their growth, shape and table qualities. Good seed should be heavy and every one well filled out. The lighter ones may be blown off or screoned out. It is a good plan to test their germinating qualities by starting one hindred seeds and seeing how well they start. For the winter or first cror. the seed is sown out of doors and transplanted airectly* into the permanent bed. For winter use the seeds are sown in flats in rows about an inch apart and then covered lightly with sand, watered and set in a favorable plage to germinate. Under the bencl:es on the heating pipes is a good plage provided care is taken to remove as soon as the young plants appear or else they are apt to become spindling. The ‘Grand Rapids Forcing seems to start better without any covering but simply to press the seeds into the soil. The beds are usually arranged wpon benches which enables the operator to care lor the plants vithout stooping ;to arrange the heating pires so that there will be bottom heat, also provides for a vetter circulation of air above ard below. The main object- ions to raised beds are the expense of construction, which is considerable, and also that the soil is soon exhausted and must be soon renewed. To overcome these objections. the solid bed is used quite extensively. A gf od drainage having been provided, a hed is built up on this some two feet. This plan gives a mich freater growing area. Personaliy, I prefer the bencnes as you have a mucn better control over heating and ventilation. The stl best adapted for this purpose is a light sandy loam as this holds water readily. dries out quickly without lumping, does not become sour if too much water is used and will hold hums and fertilizers. Unless one is quite expert, the vest fertilizer he can use is well rotted horse manure, which contains the desired elements in the right proportion. The plants voing what is known as a “leafy crop" requires considerable nitrogen, but if too mich of this one element is given to outrank the potash and phosphorus in the soil, the plants will not do as well as where the three elements are suprlied in right amounts. The plants can be set directly into the permanent bed from the seed flats. At first this seems like a waste of room , the plants wili soon require all this space. About eight inches apart scems to be about the right distance, although some of the head varie- ties require a little more room. Some advocate setting four inches apart and as the plants grow, to thin by removing every other one; but the number of flants requircd and the labor involved in the second removal will not pay in the end. The ground should never be allowe’ to become hard or baked and should be stirred every few days to allow the air to permeate the soil. This cultivation should be continued until the plants are so large as to be injured by it. In watering, care must be taken to give tne plants sufficient water and yet not so mich as to allow the ground to become soggy. As the plants increase in size, watering can be best done by means of sub-irrigation,i e when the dirt is being placed on the bench, lay from end to end a row of tile covering with the soil. In order to water, let the water run into the tile and sufficient Will leak out between the joints to moisten the earth. By watering this way all danger of the leaves rotting on account of lying on the wet soll is avoided. To se to best advantage the bench should have a tight bottom. In order to get the best results the right temperature mist be maintained. About 50°F. is best, allowing it to drop to 40° on cold nights, but sudden changes mist be avoided. Great care being taken during the warm spring days not to let it run up too hign. The growing of lettuce in pots is advocated by many growers who cater to a particular market and get top prices on their prod- ucts. The rlan is asifollows: From the flats the plants are transplanted into two inch pots and the pots are then plunged into a ped of sandy loam about one-half inch below the rims, which prevents them from drying out too quickly. They are given fre- quent waterings and care as in beds. When full grown a pot is lifted and another inserted in its place. The chief advantage of this system is in the marketing of the plants. When ready to market, the plants are lifted from the bed and placed in a tray or flat and thus sent to market. The salesman cutting off the head and returning the pots and trays or the plants may be taken from the pots and the ball of earth wrapped in oiled paper at the growers. In either case the plants arrive on the market in a perfectly fresh condition and will remai:: so for several days, which enables the merchant to keep them longer than where the neads are cut. The yield is not so heavy this way but the greater price makes up this loss. The general crop is generally marketed in crates or ventilated barrels, packed so as to prevent injury to the leaves. The essen- tial points in shipping and packing are to get as mich as possible in the case without injury to the plants and in such a manner as to arrive on the market in a fresh condition. There are not many insects which trouble this plant. The chief one is the green aphis which can easily be held in check by spreading tobacco stems and dust about the growing plant and if this is not sufficient. by burning tobacco stems once a week, the fumes of which will overcome them. Mildew, leaf rot and damping off are all generally due to too high temperature or too much water on the surface where it sours the soil and the proper conditions are then tresent for these diseases. Proper attention to watering and ventilation will generally reduce the danger from the diseases to a minimum. The main points of the growing of lettuce I have tried to touch upon in the above, but the cnly way to find out how to do it is to do it and one will soon find out that he must adapt humself to the conditions as he finds them in his own houses, and whatever methods or plans he finds makes his plants grow, those are the ones he must follow even if it is different from the method follow- ed by others. Following will be found a few original results obtained during the last year. Experiment I. Test of germinating qualities of seeds of different prades. From a commercial package of seed, three lots were select- ed, each containing one hundred seeds. These were weighed with the following results: Lot I containing I00 seeds the largest and best, weighed .175 g. Lot 2. I00 seeds as in the package .I5g¢g. Lot 3, I00 seeds, the poorest and smallest, .I2g. These were plant- ed in the oren ground and soon started, making plants suitable to transplant as follows: Lot I, 84 plants. Lot 2, 48 plants. Lot 3 24 plants. Every one of Lot I was first class, strong and vigorous. Many of Lot 3 were weak and sickly. The difference could be seen at a glance. The different lots were transplanted and grew seeadily from the first. Lost none from Lot I, while many in the others died. It shows that large heavy seed is very desirable and while it might not pay to pick it out, obtain seed that weighs as much as possible and when the secd has started, select only the more vigorous plants. The following table shows experiment in detail:- Lot Condition of Seed. No. Weight. No. of Plants Produced. I. Finest and best I00 ~L75¢. 84 2. Medium 100 .I6 g. 48 3. Poorest L100 12 g. 24 Experiment II. Experiment in watering. Comparing surface with Sub-irrigation. The plan wes to try a section of each, growing one lot by surface watering and the other by sub-irrigation but owing to lack of apace, it was confined to flats and finally when some three inches high, all plants were put into beds together. The seeds were started in cigar boxes, one watered from sprinkler, the other set in water until soil well wet. No difference was noticed in the early stage. These rlants were transplanted into flats four by four inches and original plans continued until transplanted as noted. Those that were sub-irrigated secmed to be somewhat ahead owing ho doubt, to their using all their energies in growing. Those watered from above were beaten down whenever watered which held back some also as these had to be watered every other day while the others were only watered once in five days. If the beds were arrange’ so as to irrigate, should advise that plan by all means as it is easier and better for the plants. Experiment III. To ascertain whether the plants did better when set out six by six inches or when put three by three or one and one half by one and one half inches and transplanted once or twice so that finally 211 would stand six by six inches. This experiment was not finished owing to lack of space at the proper time. It however, srows the number of plants required and the time necessary to set out each plant at rirst. r KA O Bae x kK we @ & b x + 7 RB oO 3.1/2 feet wide x % ® @ Xveoyv I long VN p DB Pvey Bcale, 1/2in.to x k K 6 yeey | | foot. ¥ x x I. > ¥ Piot A planted,6x6 in. requires 24 plants, time to plant, 15 min. Plot B planted 3x38in. requires 75 plants, time to set, 45 min. Plants marked ) removed, leaving 0 finally Plot C planted 1 1/2x1 1/2 in. requires 2°24 plants. time to set 3 hours. Plants marked ¥ removed first time, leaving @. 3x3. Plants marked @ removed second time. leaving x final growth. From the above it is estimated that to plant a bed 3 1/2 by 50 feet it would take the time and mumber of plants as indicated pelow, using the experimental plots of 3 1/2xl as a base. SS ee Plot Distance |No of plants’ {No of plants Time to | Time to in plot 3 1/2xIl required |set plot | set bed ped 3 1/2 x 3 1/2x50 50 A. @x6 in. 24 700 I5 min.| 6 1/4h B. 3 x 3 in. 75 2800 45 min.| 33 3/4 h C. I 1/2 x 224 T1200 3 hrs. | 150 h T 1/ein. 4 So it would not pay to spend so mioh time in setting so close or to use so many plants. The transplanting would take longer then the original setting. While the time required to set B and C is larger than it would be in actual practice, it will be readily seen that to set 6x6 at first is the most ecomonical way possible. However, when space is very small, mucn may be gained by setting 1 1/2x1 1/2 and as the plants grow, transplanting as in above table. Wnen set 1 1/2x1 1/2. II,200 plants can be grown in the same space as 700 set 6x6. Experiment IV. A Test With. Various Fertilizers. Diagram showing the different plots and the various fertili- 7Zers used. The soil had been in the bed two years and when enriched as indicated the third crop was put on. Fertilized with- Plot I#7 Ground Bone. if « 1/2# Sulphate of Fotash. I 2 " 3 If u " 1/2# Potash, 1/4# Nitrate of Soda. 4 2 bushels of well rotted comrost. 5 No fertilizer check plots “m ea os ee wv °° nee. a ON ee SE 0 6 POOR OTT -_—-- mk & ayes ~ 10 norco Soult: Ii On January 7. these plots were set out with plants of the "Rawson's Hothouse, a variety of the Boston Market. These plants were put into flats December. 20, 1897. They were set about 8x8 in. each plot being I0 feet long and 3 1/2 wide, containing 102 plants. On January I0 rlot 6 was made ready amd plants set; also the beds were covered with tobacco stems and dust. From now on the plants were given careful attention as to water aid cultivation. It became quite aprarent that plofgs 4 and 5 were doing the best. Plot 3 was quite noticable as peing smaller and not so healthy looking, plots 1 and 6 also quite small, on February I0, four weeks from setting out. About the first of March the plants were watered by sub-irri- gation. Plot 3 was given an extra amount of water as it had been previously noticed to always be considerably drier than the other plots. “lowever, on the time of my departure from College, March TI, the plants in the various plots seemed to be about the same size except some which were quite smaller. Plot 4 and 5 all the time seemed to do the best. 4 was fertilized with manure while had no extra fertilizer added. However. I am inclined to believe their better growth was due not so much to the fertilizers as to the fact that they were nearer the north end at which the steam Pipes entered and where it is not so exposed as it is at the south end of the forcing house. On examining the roof, I found in nearly every case where the plants were small. it was due to the fact that there was considerable crack in the glass above, thus allowing the cold air to check their growth. Over plots 4 and 5 the glass was mich tighter, part being lapped and part butted. Not being present when the crop was marketed, I could not get an idea of the difference in weight of the different vlots. However, while IZ the plot with. manure did the best, I wold not like to give the credit to that alone as there were other favorable circumstances, Great care must be taken to see that the plass is tight and no eracks to allow air to enter. The only conclusion that I would draw from the above experiment is that for the ordinary person, petter results will be obtained from the use of horse manure than where the other artificial fertilizors were used. Wnile the growing of lettuce may seem to be an easy task, yet it is beset with many difficulties which experience alone will bring out. a — 7 ‘