2396 



ORCHIDS 



ORCHIDS 



2669. Newly 

 germinated 

 seedling (Pha- 

 ius hybridus). 



normal and the atmosphere is overcharged with mois- 

 ture, very little watering or damping is needed, and 

 unless it be some particular species which cannot endure 

 drying, or tiny seedlings, it is safest to withhold water, 

 as at these times the stomata cease action and the 

 plants become overcharged with water; 

 * thus those with weak constitutions and 



j$l immature growths are liable to attacks 



*>^ of wet-spot and rot. The best means of 



counteraction in such cases is to apply 

 fire heat and ventilation. A close stag- 

 nant atmosphere is always to be avoided. 

 As a safeguard against excessive 

 changes in humidity, a hygrometer should 

 be kept in each department to ascertain and reg_ulate 

 the degrees of moisture, especially during fall and winter. 

 When overabundant, moisture can be reduced by ap- 

 plying fire heat and ventilation, and if insufficient by 

 wetting down the paths and shelves, or 

 pits, and reducing the ventilation. Well 

 regulated departments should be kept as 

 near as possible to 70 or 75 through 

 the day or 80 to 85 with free ventila- 

 tion, and about 80 at night. Just after 

 damping and watering, it will often rise 

 to 85, but this is of no consequence, as 

 it soon recedes. Orchids at rest, such as 

 calanthes and dendrobiums, should be 

 held at 65 to 75. In no case, where it 



2670. Three 

 months from 



uvm anj \ju i v t u . iii iiv< v n.^v , ai\ i v xu A A A 



can be avoided, should it go below 60 ' 

 nor rise above 90 for any length of tune, 

 as serious results are very liable to follow. 



Ventilation. 



to transfer to a 

 pot. (Paphiope- 

 dilum insigne 

 var. Sanderae.) 



The ventilators should extend the entire length on 

 both sides of the ridge, and be supplied with the best 

 modern lifting apparatus. Extending them continu- 

 ously along the roof necessitates raising them but a 

 small height to afford proper circulation to the plants 

 and egress of overheated air, without losing too much 

 moisture. Having them on both sides assists in avoid- 

 ing direct drafts, by using the side protected from the 

 direct wind. 



Air must be given at all times, when possible, to 

 keep the atmosphere active, as well as to lower tem- 

 perature, also to -reduce the density of moisture when 

 excessive in close, inclement weather and during the 

 night. In bright weather ventilate enough to allow 

 egress of the heated air. 



It is customary with some cultivators to close down 

 ventilators in wet weather and during the night to help 

 retain heat. This is a serious mistake. It may show 

 no visible injury in bright weather, when the density of 

 moisture in the atmosphere is at a minimum, but this 

 bad practice surely accounts for the decaying of many 

 young growths, which are lost during wet, close and 

 cloudy nights. 



Propagation. 



Many species of orchids can be propagated by 

 division and by cuttings. This is usually resorted to 

 when it is desired to increase the stock of rare and 



unique species and 

 varieties. With 

 the more common 

 species, however, 

 it is cheaper and 

 better to buy 

 freshly imported 

 stock, if it can be 

 had, as it often 

 requires two, three 

 or more years to 

 bring the young 



2671. Eight months from seed. plants up to the 



(Phaius Wallichii.) flowering stage. 



The pseudobulbous species, such as cattleyas, odon- 

 toglossums, coelogynes, are propagated by cutting part 

 way through the rhizome three or more pseudobulbs 

 behind the lead with a sharp knife. This will usually 

 retard the sap and force the dormant eye behind the 

 cut to grow. The back portion may then be removed 

 and potted or basketed separately, or left on the plant 

 to mature the new growth, and be removed when it 

 starts action the following season. 



With the deciduous calanthes, the old bulbs should 

 be removed when potting them in spring and put, sev- 

 eral together, in pans or flats and partly covered with 

 sphagnum or potting compost until they start to grow, 

 when they should be potted in the regular way. Thu- 

 nias are easily propagated after the young growths are 

 well advanced, by cutting the last year's stems into 

 pieces 4 or 5 inches long and inserting the ends in 

 chopped sphagnum and sand, placing them in the propa- 

 gating-house until they grow, when they may have 

 their normal heat. Dendrobiums are managed in much 

 the same way, or the old canes can be laid on wet 

 sphagnum, when many will produce new growths from 

 the side eyes on the nodes. Aerides and vandas are 

 increased by removing the upper portion with a sharp 

 knife, leaving a few roots and at least a foot of stem to 

 each top. The old bases of the stems usually break new 

 growths freely, often producing several new shoots 

 from each. Cypripediums should be divided between 

 the older growths, leaving at least one old growth with 

 each lead, and potted separately, allowing them a little 

 extra moisture until they start to grow. Masdevallias 

 and allied genera can be separated in the same manner, 

 leaving several leaves and one or more new growths or 

 leads to each piece. All species should be propagated 

 at the commencement of the growing season. 



Reproduction of orchids from seed. 



The reproduction of orchids from seed through cross- 

 ing and hybridizing has been conducted for many years 

 successfully by a limited 

 number of hybridists, princi- 

 pally abroad, and it is only 

 within about twenty - five 

 years that it has received 

 much attention in America, 

 but in that time very many 

 beautiful hybrids have come 

 into cultivation. Many of 

 our establishments, both 

 private and commercial, are 

 now paying much atten- 

 tion to this branch of orchid 

 culture, with varying degrees of success. 



The seeds germinate best when sown soon after 

 maturity, and many lose their vitality in a few months if 

 kept too dry and warm. When sowing the seeds, the 

 best results are often obtained when they are dusted 

 on the surface of pots or baskets containing a plant of 

 the same genus as the seed and carefully watered with 

 a very fine rose until they become attached, watching 

 carefully for snails, slugs, and depredators in general 

 that infest the compost. The pots or baskets should 

 have a favorable-looking surface, with the compost 

 in good condition, firm and free from fungi. Use pots 

 or baskets that will not have to be disturbed for a 

 year or more, as it often takes that length of time for 

 the seedlings to come through. Seed sown in early 

 spring seems to germinate soonest. The writer has had 

 selenipedium seedlings up in three months from sow- 

 ing, and again has waited for cypripedium twenty- 

 three months before the seedlings appeared. 



After the seedlings have perfected two or three 

 leaves it is quite safe to remove them to small pots, 

 singly, or several to a small pan, using compost of the 

 same material as that for the parent, but cut a trifle 

 finer. Many tiny seedlings are lost shortly after germi- 



2672. A year from the seed. 

 (Cattleya intermedia X C. la- 

 biata.) 



