Encyclopaedia of Gardening 241 



in involucre. . Ord. Filices). There are a few very useful ferns 

 included in this genus, notably affinis, a hothouse species ; Marantae, 

 which also likes a warm house ; sinuata ; and trichomanoides, white, 

 powdery fronds, a good basket plant. They may be propagated by 

 spores (see Ferns), or division of the crowns in spring in the case of 

 those with tufty habit. Peat, with pieces of sandstone and char- 

 coal, suits. They must have plenty of water in the soil during the 

 growing season, but not overhead. A light, airy position is desirable. 



Nuphar, Yellow Water Lily, Brandy Bottle (nu-phar, from the 

 Arabic name neufar. Ord. Ny mphaeaceae) . Nuphar luteum is a 

 hardy British plant, with yellow flowers in June. It may be 

 established in a pond by binding loam and moss round the roots, 

 and weighting with a stone to sink the mass. Propagation is by 

 division in spring. Advena also bears yellow flowers in summer. 



Nut. See Corylus and Fruit. 



Nycterinia (nycterin-ia. Ord. Scrophularineae) . Seedsmen offer 

 Nycterinia selaginoides, a dwarf half-hardy annual with blue and 

 white perfumed flowers in summer, but botanists do not keep up 

 the name. For culture, see Annuals Half-hardy. 



Nymphaea, Water Lily (nymphae-a, after nymphe, a water-nymph. 

 Ord. Ny mphaeaceae) . Beautiful aquatics, the modern hybrid 

 forms of which are well worth growing, either in shallow ponds, 

 pools, or tubs. See Flower Garden. 



Oak. Too large a tree for most gardens, the Oak, Quercus 

 Robur, is nevertheless of interest to garden lovers, because of its 

 fine effect in park and forest. It is, of course, important as a timber 

 tree. The Holm Oak, Q. Ilex; the Turkey Oak, Q. cerris; and the 

 Cork Oak, Q. suber, are not too large for fairly extensive gardens. 

 See also Quercus. 



Oak-leaved Geranium, Pelargonium quercifolium. 

 Ocimum Basilicum (Basil). See Kitchen Garden Herbs. 



Odontoglossum (odontoglos-sum, from odons, tooth, and glossa, 

 tongue, owing to the tooth-like growths on the lip. Ord. Orchida- 

 ceae). A large and beautiful genus of Orchids. Some of the best 

 kinds will thrive in cool houses, and are inexpensive. Crispum 

 (Alexandrae) is the most popular of all. Many forms of this are as 

 cheap as Fuchsias, although the rarer ones are dear. At least 100 

 forms of this species alone could be named, all of which would be 

 acknowledged by experts as good. Like most of the Odontoglos- 

 sums it is a moisture-loving Orchid, and must never be kept dry at 

 the root, even in the winter. In summer there must be abundance 

 of root and atmospheric moisture. The plants are grown in pots, 

 in a compost of peat and Sphagnum set on a base of crocks that 

 two-thirds fills the pot. The pseudo-bulbs should be above the 

 brim of the pot. When new roots show towards the end of summer 

 is a good period for repotting, or it may be done at the end of winter. 

 A minimum winter temperature of 45 will suffice, and this can be 

 maintained without hard firing if the house is adequately piped (see 

 Greenhouse Heating). In hot summer weather steps must be taken 



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