AprU 13, 1871. ] 



JOURNAL OF HORTIGULTUEB AND COTTAGE GABDENEE. 



267 







WEEKLY 



CALENDAR. 















Month 



Day 



of 



Week. 





Average Tempera- 





Sun 



Sun 









Clock 



Day 



APEIL 13—19, 1871. 



ture near London. 



43 years. 



Rises. 



Sets. 



Eises. 



Sets. 



Age. 



Sun. 



Year. 









Day. 



Night- 



Mean. 



Days. 



m. h. 



m. h. 







Days. 



m. s. 





13 



Th 



Royal Botanic Society's Show closes. 



65.6 



SB.9 



44.7 



17 



11 afS 



60 at 6 



8af3 



24 a 11 



23 



34 



103 



14 



F 



Pkincess Beathice Boen, 1857. 



67.0 



86.1 



46.6 



17 



9 5 



62 6 



42 3 



after. 



24 



19 



104 



15 



S 





68.4 



87.8 



48.1 



21 



7 6 



63 6 



11 4 



54 1 



25 



i 



105 



16 



Sun 



1 Sunday after Easter. 



57.4 



37.1 



47.3 



27 



5 6 



55 6 



31 4 



7 S 



26 



after. 



106 



17 



M 





58.2 



36.8 



47.0 



15 



2 5 



67 6 



50 4 



19 4 



27 



25 



107 



18 



Tn 



Meeting of Zoological Society, 9 p.m. 



66.8 



88.0 



47.4 



16 



5 



69 6 



6 5 



29 6 



28 



S9 



108 



19 



"W 



Koyal Horticultural Society's Spring Show, 

 [ Fruit, Floral, and General Meeting. 



59.0 



35.6 



47.3 



10 



58 4 



7 



22 5 



37 6 



• 



53 



109 



From observations taken near London during forty-three years, the average day temperature of the week is 57-5°, and its night tem- 1 



perature 86.3°. The greatest heat was 77=, on the 18th and 19th, 1854 ; and the 



;owe3t cold 20°, on the loth, 1862. 



The greatest fall of I 



rain was 0.56 inch. 







1 



GREENHOUSE PLANTS.— No. 1. 



jN tliis and subsequent papers I purpose to 

 treat of some of the plants which, from the 

 profusion and beauty of their flowers, or the 

 colours and forms of their foliage, are desir- 

 able for the decoration of the greenhouse. 

 The structure, however, having considerable 

 effect on the plants grown in it, I must first 

 allude to that. 



A greenhouse, as we accept the term, is a 

 glass structure devoted to plants not requir- 

 ing a higher temperature than is sufficient to secure safety 

 from frost ; but we have a variety of plants to cultivate- 

 some of these ilower in summer, and therefore require to 

 be kept from undue excitement in winter, and others flower 

 in winter, and need a temperature of not less than 40°, 

 though in very severe weather 35° may not be attended 

 with injury, and from 40° to 45° is the temperature which I 

 consider should be kept up for the safety and well-doing of 

 a mixed collection of greenhouse plants. Beyond this, 

 iire heat is injurious. 



As distinguished from a conservatory I think a green- 

 house is a plain structure of glass, with timber or iron, or 

 a combination of both, and walls of brick or stone. No 

 structure in the end is so dear as a fraU one. Neither 

 inside nor outside do you look for any attempt at orna- 

 mental architecture, and the size and form are variable, 

 being determined very often by the means. In a conserva- 

 tory we look for something more than a plain glass struc- 

 ture ;_ we expect it will be in size proportionate to the 

 mansion, and of a style, as regards its architecture, to 

 harmonise with that mansion. Conservatories as a rule 

 have considerable elevations— high upright fronts, and roofs 

 very much higher than greenhouses, and this loftiness, com- 

 bined with the greater obstruction to the light by the use 

 of much more massive timbers, &c., renders them unfit in a 

 great measure for the most desirable of greenhouse plants, 

 except such as attain considerable size, and succeed, as 

 do some remarkable for their foliage, in a not very light 

 structure. However, conservatories of late years have 

 been very much improved both in appearance and suita- 

 bility for plant growth; and there ought not to be any 

 material difference as regards light and ventilation between 

 a conservatory and a greenhouse, though the former may 

 be very different in size, loftiness, and architecture from a 

 greenhouse. 



As regards the form of a greenhouse, there is no dis- 

 puting the fact that a span-roof is the best ; but the lean-to 

 form is the more economical one, as very often advantage 

 is taken of a wall already built, which is a great saving of 

 first cost, and enables many to have a small greenhouse 

 who otherwise could not have one. The great drawback of 

 lean-to houses is that plants are inclined to become one- 

 sided, but they may nevertheless be grown very well in 

 such structures, yet not so good in form as in span-roofed 

 houses, which admit light on all sides of the plants. Ad- 

 mitting light to the fullest extent consistent with a sub- 

 stantial structure is perhaps the most important part of 



No. 524.— Ton. XX., New Series. 



greenhouse construction. Light on all sides of plants is 

 the way to have them symmetrical. 



The next essential of a greenhouse is the means of 

 admitting abundance of air, and to effect this the whole of 

 the front lights should be made to open to an extent equal 

 to half their height. For instance, the whole height being, 

 say 4 feet, and the lights being hinged at top, they should 

 open 2 feet at bottom, which will admit half the amount of 

 air that there would be were the lights entirely removed, 

 and just half that of lights hung on pivots. The latter, 

 when the side lights are very high, is a good mode of open- 

 ing ; the front being divided into two parts, and the lower 

 opening on pivots, as much air will be admitted as if the 

 whole height were formed into lights hinged at the top,, 

 and half opened. 



At the highest part of the house provision should be 

 made for openings quite equal to those in front, and these- 

 being provided throughout the length of the house, enough 

 air will be admitted for successful practice. If the house 

 is a span-roof it is desirable that both sides should be 

 formed so as to admit air; though this is not always done, 

 yet it is very desirable. 



As regards the construction, the front wall of a lean-to 

 or the side walls of a span-roofed house ought not to be 

 more than 3 feet 3 inches high from the floor line, and the 

 front lights of a lean-to or the side lights of a span not 

 higher than 3 feet, nor less than 2 feet 6 inches. Along 

 the whole of the front, and along both sides of a span, I 

 prefer a stage of laths, their upper surface level with the 

 bottom side of the wall plate, and 3 feet wide, taking the 

 stage all round — along both ends of a lean-to and a span, 

 wherever there is glass, except across the doors. The roof 

 I would have at an angle of 45°, irrespective of width. 

 This will give sufficient head-room over the pathway next 

 the 3-feet stage along the front and both ends, and all 

 round if a span ; and in the case of a lean-to of considerable 

 width there is no objection to a walk at the back, leaving a 

 foot or 18 inches of space for a border, so as to utilise the 

 back wall for plants. The remaining part not wanted for 

 the walk, which walk need not be more than 3 feet wide for 

 a greenhouse, may be disposed of as a step stage, the first 

 shelf being on a level with the front or side stage, and the 

 steps may be from 9 inches to a foot high, and as wide as 

 you like, only I think 1 foot quite wide enough for the first 

 shelf of the stage, and 6 inches increase for everyone, and 

 the top the width of the steps on one side, or one-third' 

 the width of the central staging. Along the whole length, 

 of the front I would have a border 2 feet deep, and staging 

 3 feet wide, for climbers for covering the roof. 



The front or side lights and the ends should have sup- 

 ports to correspond with the roof timbers, and though they 

 must be framed for opening, I should dispense with sash- 

 bars altogether, and employ extra thick uprights and rafters, 

 and instead of two, three, or more panes, have but one. 

 The roof rafters to be 3 feet apart, with one sashbar be- 

 tween each ; panes thrice as long as wide, to have no 

 lap, but straight joints, and immediately under each a 

 small cross-bar of wood chamferred, and half an inch wide, 

 let into the rafter and sashbars level with the rebate ; bed 



No. 1176.— YeL, XLV., Old Seweb. 



