ORCHIDS 



ORCHIDS 



2391 



changeable and the heat of .summers more intense and 

 less Immid, necessitating a different mode of treatment. 

 With a more satisfactory understanding of their require- 

 ments, orchid-culture here ha.s made rapid advance in 

 recent years, and most of the best collections have 

 come into existence, many of which offer a very favor- 

 able coniparLson in fine well-grown specimens with those 

 of the Old World. 



Orchid houses and their construction. 



Various are the opinions of cultivators regarding the 

 proper construction of orchid houses to secure the best 

 results. Forty or more years ago many fine specimens 

 of orchids were grown without a special house, along 

 with general stove and greenhouse plants, and many 

 good plants are still found cultivated in this way, but 

 where a general collection of orchids is grown, four 

 separate houses or divisions will be found necessary to 

 obtain the best results. These are known as the "East 

 Indian," "Brazilian," "Mexican" and "New Grana- 

 dan," or odontoglossum departments. This is the 

 older terminology, but it represents a good cultural 

 classification. 



The East Indian department requires a winter tem- 

 perature of 6.5° to 70° F. by night and 70° to 75° F. by 

 day; a few degrees' rise with sun heat will do no harm. 

 The temperature should be gradually increased 10° 

 toward midsummer and gr.adually decreased toward 

 late fall. This is the warmest house and is u.sed for the 

 cultivation of aerides, angrscums, the warmer tropical 

 cypripediums, phala-nopsis, calanthes, dendrobiums 

 and thimias while growing. 



The Brazilian department should range in winter 

 from 60= to 6.5° F. at night and about 70° F. in the day, 

 allowing a few degrees more with solar heat, and a 

 rise of 10° toward midsummer. This department is for 

 bulbophyllums, cattleyas, warm epidendrums, Brazilian 

 Islias, miltonias of the cuneata and spectabilis sections, 

 Odontoglossum citrosmum, stanhopeas, and various 

 genera and species requiring a hke temperature. 



The Mexican department is used chiefly for the culti- 

 vation of Coelogyne cristata, Mexican licUas, growing 

 lycastes, anguloas and aeinetas, many species of Max- 

 illaria, a large part of the oncidiums and warm odonto- 

 glossums, phaius and allied species which require a 

 few degrees lower night temperature and usually a 

 little more sunUght to ripen their tissue for flowering 



2656. Section of a small, well-constructed orchid house 

 heated by hot water. 



than is afforded in the Brazilian department. It is also 

 invaluable for resting dendrobiums and many other 

 deciduous and terrestrial orchids. 



The New Granadan (it might now be called the 

 Colombian) or odontoglossum department must be 

 kept as cool a.s possible in summer, and in winter should 

 range from .50° to .55° by night and to 60° F. by day; 

 it is used principally for masdevallias, odontoglossuras, 

 more especially 0. crispum, and allied genera, disas, cool 

 oncidiums, such as O. ornithorhynchum and O. varico- 

 SJttn, lycastes in warm weather, and many other indi- 

 vidual species from high altitudes which require a cool 



2657. Lean-to house with northern 

 aspect for Odontoglossum crispum and 

 other New Granadan orchids. 



house at all seasons for they suffer from the heat of 

 our summer. 



Styles of construction change, but the fundamental 

 principle in building an orchid house is to secure a 

 structure that can be easily heated and which has a 

 naturally moist atmosphere without excavating deeply, 

 for houses built much below ground lack circulation and 

 a 1 m o s t a 1 w a y s 

 prove detrimental 

 to orchid-culture. 

 The houses (ex- 

 cepting the New 

 Granadan house) 

 should preferably 

 be built to run 

 north and south 

 with an east and 

 west exposure, in 

 order that they 

 may receive the 

 benefit of the 

 early morning and 

 late afternoon sun, 

 with the least 

 possible heating 

 effects from it at 

 noonday, thus 

 making little ven- 

 tilation necessary; atmospheric moisture will be more 

 easily retained in such a structure. The hou,ses may be 

 as long as required (with the potting-shed at the north 

 end to avoid unnecessary shade and protect the houses 

 in winter against severe north wind), and about 16 

 feet wide, which will allow side beds of 2,^^ feet each, 

 two walks of the same width, and a center pit 6 feet 

 wide. From floor to ridge should be 10 feet and to the 

 eaves 4} 2 to 5 feet. Top ventilators should extend 

 along both sides at ridge, thus affording protection 

 from du-ect cold winter drafts in airing by using the 

 sheltered sitle. Side ventilation is unnecessary and 

 often injurious, the direct drafts causing plants which 

 are out of condition to shrivel. 



In glazing orchid houses, the glass should not be 

 less than 12 by 14 inches, and larger if possible. It is also 

 important that only the best quality procurable be 

 used, free from lenses which bum the leaves when 

 shading is removed. Plate gla.ss is much to be preferred 

 when it can be had, as it contains no lenses and gives a 

 pure even light. If this is used a size about 16 by 24 

 inches will be found very serviceable. Poor glass should 

 not be employed in any case, as it necessitates shading 

 long before this is beneficial to the plants. 



The outside walls should be built of brick or stone 

 when possible, and the beds and pits within should be 

 of the same material, 8 inches thick and about 3 feet in 

 height, filled solid to the top, using stone or rubble for 

 drainage in the bottom, following it up with finer 

 material and finishing with an inch or two of fine gravel. 

 Wooden benches may be used if desired, often with 

 first-class results, by covering them 2 or 3 inches deep 

 with ashes, sand or gravel, but the solid benches are 

 more sure to give better satifaction. They give off 

 moisture more gradually and offer a cool footing for 

 the plant both winter and summer, which is essential 

 and natural. 



Good results will follow from either steam or hot- 

 water heating when properly conducted. Unless the 

 range of glass is larga and a night fireman is kept, the 

 old-fashioned method of hot water under natural circu- 

 lation will be useful for orchid collections, using the 

 regulation 3 J^ 2-inch pipe, running the flows along the 

 back beneath the eaves and returning alf)ng the floors 

 beneath. (See Fig. 26.56, which fairly illustrates an 

 acceptably constructed house.) The quantity of pipe 

 required for heating a house depends upon the loca- 

 tion anil degree of heat desired. A slab or board should 



