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THE GARDENERS' CHRONICLE. 



[December 1, 1888. 



differing from that species by being more incurved, 

 and the petals and sepals not so acutely pointed. A 

 good specimen, in a basket, was in flower recently at 

 the Royal Botanic Gardens, Edinburgh. Like most 

 other Maxillarias, the cool or intermediate-house is 

 the proper place for it. F. B. 



Odontoglossum Cervantesii morada. 

 A very fine and highly coloured form of this plant 

 is now flowering at Allerton Beeches, the residence 

 of H. Tate, Esq., jun. The plant is of easy culture, 

 and the specimen here mentioned is suspended in 

 the cool house. F. A. 



THE JENSENIAN SYSTEM AT 

 CHISWICK. 



The report of the small trial of the Jensenian 

 theory with respect to the earth-protection of 

 Potatos from disease, furnished at p. 572, is both 

 very interesting and valuable. It is interesting, 

 because it exhibits something very practical done in 

 a quiet unassuming way, and with excellent results. 

 It is valuable, because it naturally points to means 

 whereby the Peronospora can be successfully com- 

 batted. 



From the first announcement of Mr. Jensen's 

 theory of high-moulding I have had considerable 

 faith in it, but for the credit of that distinguished 

 man it did prove unfortunate that several successive 

 seasons were favourable to the Potato, and unfavour- 

 able to the disease ; hence, trials of the protective 

 earthing system proved little or nothing. Now 

 that we have had a really bad season it would 

 seem, with the exception of this single, somewhat 

 late entered upon trial of the method at Chiswick, 

 no one else had tested high-moulding, and yet the 

 season proved to be exceptionally one in which the 

 plan would be subjected to the severest test. That 

 the trial at Chiswick was hardly a fair one because 

 entered upon late, is certain, although in this case, 

 unavoidable. Mr. Jensen has laid it down that the 

 actual protective earthing should be done before 

 disease spots appear on the foliage, or, at least, 

 directly evidences of such are presented that would, 

 according to his belief, ensure that the protective 

 earthing was applied ere the fungus spores had been 

 washed into the soil. Mr. Jensen stated that some 

 4 to 5 inches of soil should cover the forming 

 tubers, to prevent the spores being washed through 

 the soil into contact with the tubers. That may 

 be an essential precaution, but I believe is not so 

 necessary to the success of the protective moulding 

 as is the prevention of the rush of moisture inci- 

 dental to heavy rains, which in the ordinary method 

 of earthing invariably flows into the basin formed in 

 the soil by the swelling tubers through the cavity 

 around the stems. That cavity is always existent, 

 and is enlarged in windy weather by the motion 

 of the stems. The foliage and stems of the haulm 

 act as conductors of moisture, and a far larger 

 quantity of rain is thus carried to the tubers than 

 would be the case were there no stems, but only 

 cavities. The Jensenian moulding system in throw- 

 ing the haulm on to one side of the ridge, and 

 obliterating cavities at the base of the haulm, diverts 

 the rain into the furrows, and thus the tubers are 

 left fairly dry. I had ample evidence during the 

 past summer, when occasionally lifting roots of 

 Potatos after rain, of the way in which moisture 

 will gather in the tuber basin. Then the soil ex- 

 terior to the tuber basin would be fairly pulverised, 

 and workable, but that about the tubers would be 

 literally like mud. The swelling tubers naturally 

 force the soil outwards, and others form a sort of 

 basin, the walls of which are harder than the ad- 

 joining soil, and thus the moisture running down the 

 stems is retained, and through its instrumentality 

 the fungoid spores are brought into ready contact 

 with the tubers. That some sorts escape disease 

 appreciably under the same conditions of culture 

 can only be due, I think, to the tubers possessing 

 stouter skins, so that the action of the spores 

 is to some extent resisted. On the other hand 



it has been proved conclusively over and over that 

 Potatos grown in richly-manured soils suffer from 

 disease with double severity compared with Potatos 

 grown on unmanured soil. The reason seems to be 

 found in the rapid growth of tubers in the rich soil, 

 promoting the development of thin skins and soft 

 watery flesh. It is difficult to furnish any other 

 theory in relation to this diversity of result. The 

 Jensenian system of protective earthing seems to be 

 entirely opposed to the theory put forth a few years 

 since by Mr. Wilson, to the effect that Peronospora 

 spores or sclerotia were wintered or stored in the 

 seed tubers, and developed activity after the plants 

 had made due growth in the summer. Were such the 

 case it seems impossible that protective earthing 

 could in any way check the activity of the spores. 

 Then there is some belief that the spores are wintered 

 in the soil, but, if that be correct, it is as difficult to 

 understand how the protective earthing can secure 

 for the growing tubers comparative immunity from 

 harm. It does seem absolutely certain that the 

 spores float about in the air, and settling on the 

 foliage and stems, produce the well-known black 

 spots, or are washed into the tuber basin and thus 

 affect the tubers. But what becomes of all those 

 spores which fall upon the soil remote from, the 

 tubers, or from whence they come, still seems to be 

 veiled in uncertainty. If the protective mould- 

 ing be widely tried next year under essential 

 weather conditions, and it be found as generally 

 successful as it has proved to be at Chiswick this 

 year, very much will have been done to clear up 

 the ignorance which still prevails as to the action of 

 the Potato fungus. A. 1). 



MARKET GARDENING AROUND 

 NEW YORK. 



We believe that much may be learnt by our hor- 

 ticulturists by a careful study of the methods adopted 

 by successful cultivators in other countries, and 

 probably nowhere is the business of market garden- 

 ing better done than in the vicinity of New York. 



Mr. Peter Hendeson tells us that the reason for 

 this is possibly to be found in the fact that New 

 York, being the great depot for all the nation- 

 alities of Europe it gets from them the various 

 methods there practised ; in addition to this, and 

 which may even have more to do with it, the high 

 price of labour forces them to adopt plans entirely 

 unthought of elsewhere. Certain it is that, as far as 

 the practical work in use for cultivation is con- 

 cerned, their methods in nearly all operations are 

 mostly expeditiously accomplished. 



In the immediate suburbs of New York, where the 

 lands are rapidly being purchased for building sites, 

 many the market gardeners pay as high as 100 dols. 

 (£20 16s. Sd.) rent per acre, annually, and that, too, 

 in most cases, without a lease. All such lands, of 

 course, are cultivated to their fullest capacity, and 

 even at present low prices bring an average gross 

 income of over £200 per acre. 



A great advantage is found in having the lands for 

 growing vegetables as near to the city as possible. 

 The saving in hauling of manure is one important 

 item ; but another, and one of far more consequence, 

 is that, if the grower is near enough to the city to 

 make two or three trips a day, in such a fluctuating 

 market as New York, it is greatly to his advantage. 



Whatever kind of horticultural product is grown — 

 whether fruit, flowers, or vegetables— he that is nearest 

 the market, other things being equal, has decidedly 

 the best of it — so much so that in most cases it is con- 

 sideredby Mr. Henderson better to pay £10, or even 

 £20 per acre rent, if within one or two miles of the 

 market of a large city, than to get land ten or twelve 

 miles away for nothing. 



Many important improvements have in recent 

 years been made in culture under glass, particularly 

 in the methods in use in starting plants of Cabbage, 

 Cauliflowers, and Lettuce ; the old plan of sowing 

 the seeds for these plants in the open air in Septem- 

 ber and pricking them out in October, and keeping 

 them in cold frames, is gradually giving way to sow- 



ing in greenhouses or hotbeds in February and 

 pricking out in March, which gives a far healthier and 

 nearly as strong a plant by the first week in April as 

 those that have stood the winter. 



The plan adopted in the preparation of the seed- 

 bed appears well worthy of imitation. Only 2 inches 

 in depth of soil is used, which is made up as fol- 

 lows : — The first layer, of about an inch, consists of 

 good friable loam, run through a half-inch sieve. 

 This is patted down with a spade, and made per- 

 fectly level and moderately firm. On this is spread 

 about one-fourth of an inch of sphagnum (moss 

 from the swamps), having been dried and run through 

 a sieve, so that it is of the condition o( fine sawdust. 

 On the top of the moss the ordinary soil is again 

 strewn to a depth of about three-fourths of an inch, 

 This being levelled, the seed is sown very thickly 

 and then pressed into the soil with a smooth board. 

 On this fine moss is again sifted, thick enough to 

 cover the seed only. The bed is freely watered with 

 a fine rose. The plants are pricked out into hotbeds 

 just as the rough leaf appears. The advantages of 

 this method may thus be expressed : — When the 

 seeds of most plants germinate, and they are thickly 

 sown, the stems strike down into the soil, the roots 

 forming a tap-root with few fibres, unless arrested by 

 something. Here, then, comes the value of the one- 

 fourth of an inch of sifted moss, placed three-quarters 

 of an inch from the top. As soon as the rootlets touch 

 the moss they ramify in all directions, so that when a 

 bunch of seedlings is lifted up and pulled apart, there 

 is a mass of rootlets attached to each, to which the 

 moss less or more adheres. To the practical gardener 

 the advantage of this is obvious ; the tiny seedling 

 has to begin with a mass of rootlets ready to work 

 which strike into the soil at once. The advantage 

 of the moss covering of the seed is not so apparent 

 in the matter ot a free-germinating seed, such as 

 Cabbage, as in many others ; but in many families of 

 plants it is pronounced to be of the greatest value. 



With regard to general culture, it need only be 

 said that every year brings out some improvement in 

 varieties. Within the past dozen years many im- 

 portant advances have been made in earliness and 

 in the quality of the vegetables grown. 



Quite a number of the market gardeners are 

 now getting to grow Strawberries in conjunction 

 with their vegetable crops, by following the pot- 

 layering system, by which a crop of fruit is obtained 

 in less than a year from the time of planting. 



The question of fertilisers for the use of the 

 market garden is now becoming a very serious one 

 for the market gardeners in such cities as New York, 

 where the manure from the stables does not increase 

 in the ratio of the increase of the lauds cultivated, 

 as perhaps half of all the products grown are shipped 

 to adjacent towns and cities. 



Still there are few market gardeners who do not 

 use stable manure, which costs, when fit to go on 

 the land, from 2 dols. (8s. id.) to 3 dols. (12s. Gd.) 

 per ton. This is put on in spring at the rate of from 

 50 to 75 tons per acre, to which is often supplemented 

 half a ton of Peruvian guano or bone-dust, which is 

 harrowed into the land after the stable manure has 

 been ploughed in. 



A great variety of fertilisers are used besides 

 Peruvian guano and bone-dust, such as fish guano, 

 dried blood, blood and bone fertilisers, together with 

 superphosphate of lime ; but the majority of culti- 

 vators prefer pure bone-meal or Peruvian guano to 

 all others. Garden and Forest. 



CHEILANTHES. 



The most useful species of this genus are those 

 which are sometimes found under a separate generic 

 name, viz., Myriopteris, yet I believe they are better 

 known as Cheilanthes, and are generally found under 

 that name in nursery catalogues. Although the 

 Cheilanthes can hardly be classed with Ferns useful 

 for ordinary decorative purposes, the peculiar beauty 

 of their somewhat slender fronds renders them indis- 

 pensable in a collection ; they also afford distinc 

 shades of colour. C, elegans is one of the most 



