March 17, 1906 



HORTICULTURE 



321 



teeted. In the South, where winters are milder they 

 can survive the year round in the open ground, and 

 hence field crops, especially tomatoes, are often seriously 

 injured by them. 



The problem of control is not difficult. A sharp out- 

 look must be kept up to insure prompt attention when 

 the first signs of trouble appear. With greenhouses that 

 are idle in the summer the soil may be rid by closing 

 the houses tight and forking over the soil a few times 

 during the summer. The temperature will go up to 

 150 degrees and this thorough drying out will "fix" 

 the worms. On the other hand, freezing will destroy 

 large numbers. The most practical method, to date, 

 however, is to sterilize the soil.* 



It must be borne in mind that in transplanting roses 

 or violets a certain amount of the old soil remains and 



if this is badly filled with nematodes, infection of the 

 sterilized soil will rapidly follow. The only way to 

 secure complete immunity would be to raise cuttings in 

 sterilized sand and plant out-doors in new land where 

 there can be no possible contamination from old green- 

 house soil or infested manure piles. 



In fields liming the soil at the rate of three tons 

 unslacked lime to the acre is helpful. Catch crops as 

 mustard can be sown and when plentifully covered 

 with galls pulled and burned. Both these methods will 

 not rid the soil, merely keep the worms in check. A 

 I ii •!( or way is to break up new ground and abandon the 

 old for a few years. 



•See "Horticulture," December 9, 1905. 



ai 



Azaleas 



Notwithstanding azaleas, with the exception of the 

 Indian species, are deciduous they may be looked upon 

 as among the most beautiful hardy shrubs. The low 

 lands of many parts of New England are scenes of 

 enchanting beauty when the swamp pink, Azalea vis- 

 cosa, is in newer. These make beautiful groups when 

 transplanted into favorable spots on the pleasure 

 grounds. Another species that delights the lovers of 

 flowers is Azalea pontica which grows in rich abun- 

 dance on the Pontine marshes of Asia. Azalea pontica 

 is a much more " robust grower than the American 

 species, but while its flowers are larger and more con- 

 spicuous the wood is stiff and the bush less graceful, 

 nevertheless it is as hardy as our native species and as 

 easily grown. The original variety has yellow flowers 

 but the skill of the hybridist has produced a numerous 

 family of many shades of color, from pale lemon, 

 orange, and red to scarlet, or approaching thereto. A 

 new race, imported from Japan, planted in the Arnold 

 Arboretum, surpasses in brilliancy of coloring any yet 

 seen, and is destined to make a sensation in the floral 

 world. Azalea mollis is also very beautiful, bearing 

 large flowers of a soft, delicate salmon which are very 

 attractive. The hybrid varieties of the azalea are legion, 

 and the variations of color and markings full of 

 interest. 



The azalea may be propagated in several different 

 ways, this part of their cultivation being usually left 

 to the nurseryman. The ordinary way, and the most 

 certain, is by layers which root the second season. 

 Some species can be increased by division of the roots. 

 Grafting of the choice varieties upon the more vigorous 

 species is greatly practical, because the plants are thus 

 made more compact, symmetrical and floriferous. New 

 varieties are raised from seed winch lias been pollen- 

 ated either by insects or artificially. All the processes 

 of propagation are rather slow hut when the plants 

 commence a healthy growth they soon make up for 

 the tardiness in starting. Azaleas are not quite so 

 particular as to soil as are rhododendrons; they do 

 not absolutely require peat earth but will thrive on 

 light sandy loam, but that must be enriched by a 

 strictly vegetable fertilizer for. like the rhododendron, 

 they can ho easily killed by the application of animal 

 manure especially if it is, fresh and unfermented. They 

 are, however, more at home in swamp muck and should 

 always have a proportion of it when it is possible to 

 procure it. 



In laying out what in England is called an American 

 plant garden, rhododendrons and azaleas should bo 



planted in close proximity to each other, because the 

 colors are so different; the rich crimsons, deep purples, 

 pale rose and pure white of the rhododendrons either 

 blend, harmonize, or contrast with the yellow, orange, 

 rcfl pink, or scarlet of the azaleas and the effect is 

 magnificent. 



For cut flowers for house decoration azaleas are very 

 useful and may be employed with good effect, lending 

 themselves well" to artistic arrangements in combination 

 with suitable green. In this respect they surpass the 

 rhododendrons, the trusses of which are too large when 

 cut. For very large decorations they should be used 

 as entire plants; well grown, dwarf bushes full of 

 flowers are very striking under artificial light. Another 

 reason for their use only in this manner is that the 

 branches of a rhododendron cannot be cut without in- 

 juring the symmetrical shape of the shrub from which 

 it will never recover. 



The hardy azaleas are capable of forcing and if dug 

 in the fall and placed in a cool cellar, they can be 

 brought in to the conservatory at intervals where they 

 will bloom freely and add greatly to the beauty of the 

 display. 



I remember well when the only two Indian azaleas 

 extant were Indica alba and purpurea, but these were 

 of tall, straggling habit and not capable of being 

 grown into well formed specimens. Then came a new 

 variety, A. exquisita ; this had better-formed flowers 

 with elegant pencilling^ in the upper lobe of the blos- 

 smii and of dwarf, compact habit, and from these all 

 the magnificent varieties we now possess have sprung. 

 In Indian azaleas the plant breeders and selectors 

 seem to have done their best and for compactness of 

 growth, prolific blossoming, and easy culture, for the 

 conservatory and dwelling house, it is doubtful if they 

 ran be surpassed by any" other decorative plant. The 

 Belgians may be credited in part with effecting this 

 improvement, and the cultivation and sale of tin 

 species has become of great commercial import 

 As the roots of azaleas are all fibre a very fine mix- 

 ture of black earth and sharp sand is essential lo 

 their successful cultivation. All powerful fertilizers 

 must be avoided, perfeel drainage must be made, and 

 the plam ii"i watered so freely as to cause the soil to be 

 siiddened wit li moist u re. 



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