SOIL 



In potting plants, experienced gardeners make pot- 

 ting mixtures or add a variety of materials to the soil 

 to suit the requirements of dilferent plants. For young 

 seedlings or for freshly rooted cuttings, the compost 

 should be of a light and porous nature, but as plants 

 increase in size and vigor a heavier and richer mixture 



SOLANUM 



1677 



2335. Solandra grandiflora (X 1-5). 



is usually given, that is, if plants are to be grown on as 

 specimens; but the proportion of nutrient substances 

 used in a potting mixture should be determined by the 

 vigor of the plants. It is always better to use too little 

 plant-food than too much; if too much is used it often 

 becomes available faster than the roots of plants can 

 absorb it, and hence causes organic acids to form in the 

 soils which are fatal to the roots of most plants. Many 

 amateur plant - growers in their over-anxiety to grow 

 fine plants make this fatal mistake. 



In most gardens the greenhouse space is limited, and 

 a gardener cannot always develop his plants to their 

 fullest capacity or he has to reduce his variety and 

 numbers. For instance,. we used to grow fancy pelargo- 

 niums three and four feet in diameter, but we found we 

 either had to grow smaller specimens or reduce the va- 

 riety of our collections. This, then, determines in the 

 mind of an experienced gardener the composition of his 

 potting mixtures. His aim should be to grow the finest 

 possible specimens in the smallest possible pots and 

 space, and all the cultural details given by the writer 

 in this Cyclopedia have been with this idea in mind.' 



Edward J. Canning. 



SO J A. Consult Soy Bean and Glijcine. 



SOLANDRA (after Daniel C. Solander, a Swedish 

 naturalist and traveler, 1736-1786). Sotandcece. A ge- 

 nus of about 4 species of woody vines native to tropical 

 America, with simple, entire, shining leaves and large, 

 white, solitary, datura-like flowers: calyx long-tubular, 

 2-5-cleft ; corolla funnel-shaped; tube cylindrical; 

 throat obliquely and widely bell-shaped; lobes broad, 

 imbricated; stamens 5, inserted on the corolla-tube: 

 berry globose, pulpy. 



A. Plant becoming IS-SO ft. high. 



grandiflora, Sw. Fig. 2.3.35. Lvs. obovate - oblong, 

 acute, glabrous, thick: fls. fragrant; corolla twice as 

 long as the calyx, not contracted at the tliroat, white or 

 somewhat yellowish. B.M. 1874. 0.0.111.21:272. Gn. 

 53:1161. J.H. III. 34:123. 



AA. Plant about 2 ft. high, with trailing branches. 



longifldra, Tussac (S. l<^eris, Hook.). Lvs. oblong- 

 ovate or obovate, acute; petioles purplish: fls. fragrant; 

 corolla usually 1 ft. long, three tinies as long as the 

 calyx, contracted at the throat, white or somewhat yel- 

 lowish. B.M. 4345.-Cult. in S. Calif. 



S. guttata, D. Don, has bright yellow fls. with streaks of pur- 

 ple in the throat and is longer and more sloiuler tliiiu .V. i/ran- 

 diflora and the lobes are more conspicuously fringed. Mex. 

 B.R. 18:1551. p. W. BARCLAY. 



Solaudras are attractive plants and their needs are 

 simple. A warm greenhouse — one in which the tem- 

 perature is never allowed to fall below 50° — will suit 

 them very well in the eastern states. The plants would 

 probably do well outdoors in Florida and the far South. 

 They like plenty of light and sunshine at all seasons of 

 the year, and water should be given freely from early 

 autumn till the latter part of spring, as they make their 

 growth and bloom during that period. In summer, 

 when the wood is ripening, a dry state is preferable for 

 them. The soil that gives the most satisfactory results 

 is a good, somewhat sandy loam. It is unwise to dis- 

 turb the roots of established plants more frequently 

 than is necessary. The chief point in growing Solan- 

 dras is to obtain short, sturdy branches, for those of 

 rank growth seldom or never develop flowers; fortius 

 reason the use of rich soils and strong fertilizers should 

 be avoided always. Propagated by cuttings of firm 

 young shoots taken with a heel and placed in slight bot- 

 tom heat. 



Solandra grandiflora is perhaps the best of the ge- 

 nus. The flowers do not last more than four or five 

 days. They are of a pretty greenish white color wheij 

 they first open and turn slowly to a rich brownish yel- 

 ^^'^ Michael Barker. 



SOLANUM (Latin, solamen, solace or quieting). 

 Nightshade. Solanum, giving name to the family 

 Solandcece, is a vast genus of temperate and tropical 

 herbs, shrubs and even trees, but is comparatively poorly 

 represented in temperate North America. Dunal, the 

 latest monographer (DC. Prodr. 13, pt. 1), in 1852, rec- 

 ognized 901 species, and many species have been de- 

 scribed since that time. The genus finds its greatest- 

 extension in tropical America. Of the vast number of 

 species, barely 25 are of much account horticulturally, 

 and half that number will comprise all the species that 

 are popularly well known. One of these is the Potato, 

 Solanum tuberosum, one of the leading food plants of 

 the human race. The genus seems to abound in plants 

 with toxic properties, although its bad reputation in this 

 respect is probably exaggerated. 



As a genus, Solanum is not easily separated from 

 other genera, but some of its most designative char- 

 acters are as follows: Lvs. alternate: inflorescence 

 mostly sympodial and therefore superaxillary or oppo- 



2336. Tuber of Potato— Solanum tuberosum {X^Q. 



site the lvs.: corolla gamopetalous and rotate or shal- 

 low-campanulate, plaite<l in the liud, the limb angled 

 or shallow-lobed: stamens usually 5, inserted on the 

 throat of the corolla, the anthers narrower or elongated 

 and coiinivent and mostly oi)ening by an apical pore or 

 slit: ovary usually 2-liiculed, ripening into a berry which 

 is sometimes inclosed in the persistent calyx. The fls. 



