I 



THE GARDENERS' MAGAZINE. 



Apeil 20, 1912. 



LETTUCE CULTURE* 



In a lecture recently delivered at Brad- 

 ford Mr W. F. Giles dealt with various 

 aalad plants, but paid special attention to 

 lettuce culture. 



^He^ pointed out that among salad plants 

 the lettuce is usually considered the most 

 important. In its many varieties the cos 

 type proves itself to be extremely useiul, 

 and under various conditions of culture can 

 be had practically all the year round. 

 Generally speaking, lettuces may be divided 



into three" groups: , . , ^, 



(1) Winter lettuces — that is to say, those 

 which when sown in the autumn in a fairly 

 sheltered position will stand through the 

 winter, and heart up in spring and early 



summer. . iv . ■ 



(2) Spring, or forcing lettuces — that is, 



those which when sown in gentle heat early 

 in the year, and either grown entirely under 

 el'iss or planted out on a hotlx^d, heart up 

 veVv 'quickly, but, generally siKvaking, do 

 not remain m condition long before running 



to seed. . • i_i n 



(3) SunniuT lettuces — that is, those usually 



sown ill tlu- spring and summer and grown 

 in the oi>en to provide a supply all through 

 the summer and autumn. 



It is however, difficult to draw any hard 

 and fast line loetween these sections, because 

 with tyo large a number of varieties, there are 

 some which <h> it*>t^ perfectly fit into either 

 section but it inav be taken that broadly 

 speaking, varieties 'that do well in one class 

 are not of much use in another. There are, 

 of course, exceptions, especially with the 

 cabbage varieties, but, although the cos 

 type la useful for sowing in autumn or 

 spring, it is not of so much value in the 

 forcing section. 



If these so-called winter varieties are sown 

 towards the latter part of August and in 

 September, and planted out in October and 

 onwards on some well-drained ground, tliey 

 will usually go through most of the winters 

 experienced in England, although in excep- 

 tional weather it is as well to give them a 

 little protection. 



llie deep English pattern frames are 

 usually planted with the forcing type of 

 cabbage lettuce. This is the style of culture 

 which may be seen in many English gardens 

 early in the spring, and differs from the 

 French method, chiefly in the type of the 

 frame, the hotbed, and the fact that the 

 lettuces are grown by themselves instead of 

 with other crops as in France. This being 

 the class of culture in which the French 

 gardener excels, Mr. Giles gave a few notes 



on his methods. i . v ^ 



About October he forks over an old border 

 or spent hotbed and sows his lettuce seeds 

 under the cloches or bell jars. These cloches 

 are really very useful articles. They are 

 made in various sizes and shapes, and admit 

 liffht on all sides. Some are made with a 

 knob at top, others not. ITie form without 

 the knob is that mostly in use around Paris; 

 the others are more generally used m the 



South of France. 



As soon as the seedlings are large enough, 

 they are pricked out under other cloches, 

 about two dozen under a glass. This is to 

 encourage root action, and the plants remain 

 here until they are wanted for their hnal 

 quarters in January or February If the 

 weather is at all severe, mats made of rye 

 straw are rolled over the cloches, or dry 

 litter is placed around for protection. Ihen 

 about January or February the French gar- 

 dener commences to make up his hotbeds. 

 He does not make them as many do in -Eng- 

 land entirely above ground, but digs out 

 his soil where the bed or beds will be, to 

 a depth of nine or twelve inches. Then he 

 places in the trench manure made of old 

 and new in about equal parts to a depth ot 

 one, two, or three feet, according to the 

 season and to whether he requires the bed 

 for vegetables and salads, or melons. W hen 

 the manure is well trodden down, about four 

 or five inches of good soil is placed on the 

 top and the whole is then ready for sowing 



or planting. • j. u • 



Thi advantage, of course, is that being 



below the level of the ground it retains its 

 heat much longer than would otherwise be 

 the case. The bed having been made ready, 

 it Is then sown broadcast thinly, with carrot 

 and radish seed, and planted with lettuces. 

 Usually under a cloche one cos and three or 

 four cabbage type are put, and cos are also 

 planted between the cloches. 



The beds are made in the same way and ot 

 the same size, whether they are to be fitted 

 with cloches or frames. The French frames 

 are made much more shallow than the usual 

 English patterns, so that the plants may be 

 ffrown near to the glass, and thereby not 

 become drawn. In the frame four crops may 

 be growing together, radishes, cabbage let- 

 tuces, cos lettuces, and carrots. The rad- 

 ishes come off first, then the cabbage let- 

 tuce, after this the cos, which then givee the 

 carrots plenty of room to develop; and 

 whilst they are growing plants of cauliflower 

 are put oiit amongst them, so as to occupy 

 the ground after the other crops are cleared. 

 The^^ shallow frames are really very useful 

 and quite cheap, and if they are required 

 for taller growing plants, they can be raised 

 at the corners \vith flower pots or bricks, and 

 manure put round at the bottom to keep out 

 the cold. Tlie gentle warmth from the hot- 

 beds, combined with copious waterings 

 causes the crops to grow very quickly, and 

 it is this quick growth which makes them so 

 tender. It does not do to have much heat 

 for salads, otherwise the lettuces become 

 flabby and the radishes run to foliage. The 

 French gardener finds about 55 to 60 degrees 



is quite enough. j. . f 



There is no doubt whatever that a tew oi 

 thet^e cloches, or a shallow French frame, are 

 useful things in any garden, as by their 

 means salads can be grown very quickly, 

 and therefore very tender; besides which, 

 they can be produced at seasons of the year 

 which would be almost impossible without 

 them, or unless one had house room; but I 

 should be one of the last to advise everyone 

 to take up French gardening on commer- 

 cial lines, for, although a large number of 

 crops can be produced from a small area of 

 ground, there is a good deal of work and 

 anxiety, besides expense, attached to it. The 

 system, however, is good, and, attempted on 

 a small scale, would enable one to obtain a 

 good deal out of a small space. 



Whilst on the subject of frames, I should 

 like to refer to the kind of light that le 

 used in Holland. It is made of a single 

 sheet of glass which slides in a groove, and 

 is kept in position by two blocks of wood at 

 the bottom. The lights are about 60 inches 

 by 32, and are used on shallow frames similar 

 to those used in France. The great advantage 

 is that there is no obstruction to the light, 

 and no drip caused by glass overlapping. 



The disadvantage is that if you have an 

 accident vou have broken rather a large pane 

 of glass,* but in Holland, although the men 

 wear sabots, or wooden shoes, it is not often 

 the lights get broken. Tliey can, as will be 

 gathered, be made very cheaply. Thousands 

 are sometimes to be seen in one place, and 

 thev are almost exclusively used for small 

 salads and cucumbers. 



The next class of lettuce is probably tlie 

 one most generally grown — the summer kind. 

 Of these the number of varieties is very 

 large, sufficient to satisfy all tastes. Jn 

 addition to the cos and calDbage types of let. 

 tuce, there is a class which is not often seen 

 in this country. It is the "cutting" lettuce, 

 and is much grown in some parts of America, 

 and also on the Continent. It does not make 

 a head, but produces a considerable qnantity 

 of tender salading. It is very useful for 

 spring or autumn sowing. 



SUNSHINE AND FOG. 



At a recent meeting of the Royal Society of 

 Edinburgh, an interesting communication on 

 *' The vSun as a Fog Producer was read by 

 Mr. A- Watt, on behalf of Dr. John Aitken^ 

 F.R.S., who was unable to be present. Some 

 years ago. Dr. Aitken said, it was noticed 

 by him that at Falkirk fogs frequently began 

 to form in the mornings ]ust at sunrise, and 

 observations of all the meteorological condi- 

 tions were begun to see if their appearance 

 was in accordance with any laws in nature, 

 or were what are generally called fortuitous. 

 Observations were thereiore made of the 

 humidity of the air at the time, as it always 

 plays an important part in the formation of 

 fogs. As the fogs were probably produced by 

 some impurities in the air, the direction of 

 the wind was noted, so as to ascertain 

 whether the air came from polluted areas or 

 not; the velocity of the wind was also ob- 

 served, as it would determine the degree of 

 concentration of the impurities. The trans- 

 parency of the air, that is, the amount of 

 haze or fog, was also observed before and 

 after sunrise, also the amount of sunshine in 

 the morning. Tliese observations have been 

 made during the last four winters. Tlie re- 

 sult oi the observations shows that when 

 the wind Avas light and blew from an impure 

 direction— that is, brought air from densely 

 inhabited areas and was damp— a fog invari- 

 ably formed if the sun shone ; whilst it did 

 not form if there was no sunshine ; also that 

 if the wind was from a. pure direction the 

 sun had no effect on it. The rest of the in- 

 vestigation deals with the way in which the 

 sun acts on the impurities in the atmosphere 

 and causes haze and fog, and with some sug- 

 gestions as to their prevention. 



As these fogs were thus shown to be caused 

 by some impurities in the air coming fror 

 the densely inhabited areas, an investigation 

 of the impurities in the atmosphere coming 

 from these areas was begun to try to find out 

 how the sun acted on them and caitsed tog- 

 ging. As the air coming from the polluted 

 areas contains a large amount of the products 

 of the combustion of coal, attention was 

 directed to them, and from the well-known 

 products of combustion of sulphur, attention 

 was first directed to it, as all coal contains 

 a large amount of sulphur which is burned 

 with the coal, and gets mixed and carried 

 alo'ng with the passing air. 



Among the gases in the air produced by 

 the combustion of coal which change tne 

 sulphur products to the solid or liquid con- 

 dition, it was found that ammonia, hydrogen 

 peroxide, and ozone all acted powerfully. 

 Their action, however, plays no part m tne 

 morning fogs, because the sun has no action 

 on them, and they can act on the sulphur 

 products in the dark. The products from a 

 clear coal fire and also from a coke fire ^ere 

 tested and found to act exactly like the pro- 

 ducts of burning sulphur. If tbe pr^^^t^ 

 from the fire are filtered, so as to remove 

 all particles, and then exposed to the act-ion 

 of light, radium, etc., they give a very dense 

 condensation, due to the particles tormea uy 

 the light out of the sulphur products iron 

 the fire. When, however, the P/oducts or 

 combustion of ordinary household gas we 

 tested in the same way, it was found tnd 

 neither light nor any of the other ^^^^^f^t 

 had anv IfEect on them, and they remained 



free from all particles whicli cause naz^ " 



fog. 



-bably 

 directly in tlie 



Helenium Riverton Gem. — 



Under the dry burning conditions experi- 

 enced last summer, this proved so satisfac- 

 tory that it can be well recommended for its 

 floral display. It reaches a height of ahout 

 fouir feet, and continues to bloom from the 

 latter part of July till the autumn is well 

 advanced. When the flowers first open they 

 are of a warm terra-cotta tint, but after a 

 time they change considerably to more of a 

 wallflower-like hue.— W. 



It is pointed out that these sunshine jog 



- - - caused by the sun ac "ig 

 ........ ... manner shown on the produ^^J 



of the sulphur in the coal, and also to 

 sunshine forming hydrogen peroxKie lu 

 air. This gas, as shown, combines ^itii ^ ^ 

 products of the sulphur and forms P^^" 

 which can condense vapour m ^^^^^^^ f .-m. 

 air, which accounts for these sun togs i 

 ing in air that is not saturated, ^J^''^.^^^ 

 pure air fogs only form when it is satiu 

 One conclusion pointed out is that tm 

 we may have smokeless fires a"d lurn. 

 yet we will he subjected to these to?^' t 

 in order to be rid of them we must pr^ ^^^^ 

 the escape of the invisible products oi 

 sulphur. 



