July 11, 1908 



HORTICULTURE 



35 



Primula Kewensis 



This beautiful hybrid Primula which originated as a 

 cross between P. fioribunda and P. verticillata (the 

 Abyssinian Primrose) is certainly worthy of cultivation 

 and deserving of a place in any collection, even if only 

 from the fact that it possesses yellow flowers, which 

 color is unusual amongst winter flowering Primulas. 



However, the color of the flowers is not the only 

 charm which the plant possesses; its very habit at- 

 tracts attention as it stands out erect from amongst a 

 group of other plants and even when isolated it still 

 forms a very beautiful decorative greenhouse plant, as 

 the accompanying photograph will show. It is of per- 

 ennial character, but dors best when grown as an 

 annual. 



Primula Kewensis is easy of cultivation, certainly as 

 easy as P. obconica, and this fact alone ought to make 

 it very popular, which in some gardens it undoubtedly 

 is. Seeds may be' sown at almost any time of the year, 

 but if two sowings are made, one in May or June and 

 the second in September or October, these will furnish 

 plants in bloom from Christmas until the end of the 

 following June. 



In the greenhouses of the Department of Horticul- 

 ture at Cornell University are plants which have been 

 in bloom since the middle of March and at the time 

 of writing (June 11) they are still at their best. The 

 seeds were sown about the beginning of last October. 



CULTUEE 



The method of cultivation is as follows : The seeds 

 should be sown in clean well drained pots or pans (5 

 inches is a good size), filled with a compost of one part 



each of loam, leaf soil, and silver sand passed through 

 a 1-4 in. sieve, and a layer of very fine soil placed on top k 

 The seeds which are very small should be covered 

 lightly with fine soil, a fine sieve being used for this 

 purpose. When the seeds are sown the pans should bft 

 soaked in water which will rise by capillary action, this 

 being much better practice where small seeds are con- 

 cerned, than watering overhead. 



It is best to cover the seed pans with a piece of glass 

 and to shade from strong light until germination takes 

 place. When the seedlings are large enough to handle 

 they should be pricked out into larger pans ; thence sub- 

 sequently transferred singly into thumb pots and potted 

 on as recpiisite into larger pots, until the six inch size 

 is reached, which size is large enough for their require- 

 ments, using one part each of loam, leaf soil, and sand 

 dining each potting operation, and potting moderately 

 firm. 



During the growing period the plants should be 

 placed on shelves 18 inches or so from the roof glass, 

 and the temperature of the house should range if pos- 

 sible, between 50 and 75 degrees F., never allowing a 

 fall or rise beyond these extremes. Care should be 

 taken in watering, as Primulas resent stagnant soil 

 moisture. 



FERTILIZING 



After the final potting, when the pots are filled with 

 roots an application of Guano or Clay's Fertilizer, an 

 ounce to the gallon of water, twice weekly, will greatly 

 benefit the plants, and the effect will be noticed in the 

 resultant vigor, and deep green color of the foliage. 



The plants should be shaded at all times from bright 

 sunlight, and protected from draughts, whilst an occa- 

 sional spraying with the syringe during dry weather 

 will aid them greatly, but during dull weather spraying 

 must be discontinued or damping of the foliage will 

 result. 



If the cultivator pays attention to the few details 

 mentioned above there will be no doubt as to his ulti- 

 mate success in the cultivation of this most beautiful 

 winter flowering plant. 



/ 



Conservatories of H. ]. Heinz:, 

 Pittsburg, Pa, 



Our frontispiece this week shows the central portion 

 of the ornamental range of U-Bar greenhouses on Mr. 

 H. J. Heinz' beautiful grounds at Pittsburg, Pa. 



The circular curvilinear palm house is imposing in- 

 its effect, and has an unusual ornamental simplicity. 



The passages connecting the palm house to the wings 

 on either side, seem to further emphasize this feature, 

 while carrying the wings far enough away from the 

 palm house to obviate its casting any shade on them, 

 and making excellent torn or propagating houses. Such 

 an arrangement is admirable planning, and although in- 

 creasing the cost, it is warranted by the additional' 

 returns possible. 



