458 THE ROCK GARDEN. [April 



rosette of leaves, not larger than a shilling, above ground, push their 

 roots to a distance of fully a foot to 18 inches in length. This 

 shows the necessity of having the soil deep. Very few alpine plants 

 thrive well in shallow soil, they are so much more easily affected by 

 drought, and consequently require more than double the attention 

 in respect to watering than if they had been planted in deep soil. It 

 is also a good plan to lay a few flat stones on the surface of the soil, 

 close round the plant, to prevent evaporation and keep the roots 

 cooler and the soil moist. Primroses must have plenty of water 

 during the growing season, and be kept pretty dry during the winter, 

 as on their native hills. They are very easily damped off at the 

 period when they are at rest, so the beds should be raised con- 

 siderably above the level of the soil, and a quantity of good 

 drainage laid at the bottom. On the top of the drainage place a 

 mixture of equal quantities of light loam, leaf mould, and coarse 

 river sand to the depth of from a foot to 18 inches or more. 

 Primulas are never so safe in winter as when covered with snow, as 

 this keeps them dry ; a bell glass, raised an inch or two above the 

 soil to give air, helps to throw off some of the superabundant 

 moisture; but where the rare and small varieties are grown, a 

 duplicate of each species of variety should be kexDt in a cold frame, 

 in case of any accident happening to those left outside during the 

 winter. See also that the lights of the frame are water-tight, as 

 any drop into the inside is very injurious. 



THE PROPER SOIL 



is, says Mr. Boyd, a mixture of loam mixed with the leaf mould 

 and sand, especially the smaller sized ones, as they cannot be firmed 

 sufBciently without it ; besides, they do not suffer so readily from 

 drought with this mixture. The larger growing sorts, such as 

 Primula Parryi, Stuarti, nivalis, Turkisfxinica, CasJwicriana, longi- 

 flora, Sil-l'imcnsis, gmndis, and hitcohi, do well in the leaf mould 

 and sand. 



SPECIFIC VARIETIES. 



Primula vulgaris, one of the sweetest and most beautiful of our 

 spring flowers, likes partial shade. In limestone countries the cow- 

 slip P. vcris takes its place. The oxlip P. clatior is much rarer, 

 and occurs wild only in a few places in England ; it is, however, 

 pretty common in Switzerland. Many of the hybrids between 

 P. vulgaris and vcris have oxlips, but the true oxlip has a trumpet- 

 shaped flower, and not flat, as in the Polyanthus ; it has also no 

 thickening at the moutli of the tube, as in P. vuljar.is. Our garden 



