May, l !' l i 



T 1 1 E ( J A It 1 ) E N M A G A Z I N E 



241 



At this point , if plants arc procurable, 

 they should be planted at points where 

 crevices will be formed when the nc\t layer 



of rocks is set. To prevent the roots of 

 these plants from becoming crushed by the 

 rocks which are placed on top, place a 

 couple of small stones on each side of the 

 roots of each plant. Trail the roots back 

 just so far as they will go so as to insure 

 their firm hold of the soil, and prevent their 

 unduly drying out. At the same time see 

 that the rocks of each tier incline back- 

 ward, thus directing the drainage to the rear 

 of the wall and so conserving moisture. 



In the setting of each layer, see that the 

 surface of the wall recedes. This will avert 

 toppling in the event of settling, which 

 usually occurs. 



The soil in the pockets should at all times 

 extend back to that at the rear of the wall, 

 or it will become too dry to support the 

 plants. Actual connection with the sup- 

 porting soil ensures a constant supply 

 of at least some moisture. 



Be careful in striving to satisfy the plants, 

 needs that the wall is not weakened. The 

 pockets where the plants are set should not 

 be too large, and as there will be some set- 

 tling the rocks must be selected with some 

 intelligence, and again in placing them. 



This method of construction and planting 



may not only be applied to retaining walls 

 but is as practical for use in constructing 

 steps leading up from rock gardens, sunken 

 gardens, dells, etc. 



The best side for a wall to be planted in 

 this way is seldom a matter of control, but 

 when we have a northeastern or north- 

 western exposure, or any intermediate 

 point, we may count ourselves lucky as 

 success is then assured. Some slight shade 

 is also desirable. A specimen tree or two, 

 of spreading character, will give protection 

 to some of the shade-loving plants, which 

 may be grouped at a point where they will 

 enjoy the advantage. 



The ultimate success of a wall garden 

 depends on the selection of the plants used. 

 It is impractical to consider any but those 

 belonging to the rock garden group — plants 

 which do not make a rank growth and 

 require quantities of moisture and soil. 

 Of such there is a large assortment from 

 which to choose. 



To classify them most satisfactorily a 

 grouping according to color is best, as the 

 periods of bloom are not extended over 

 long seasons, the majority flowering in 

 the spring and early summer. The follow- 

 ing are among the most easily grown : 



White Flowers. — Early in April, 

 almost before the snow has left us, the white 



moss pink (Phlox subulata, var. alba) is in 

 full flower, making a carpet of pure white. 

 At about the same time the rock cress 

 (Arabis albida) and snow-in-summer (Cer- 

 astium tomentosum) are giving forth quan- 

 tities of flowers of the snowiest white. 

 These are both low-growing plants. The 

 popular hardy candytuft (Iberis sempervi- 

 rens) it is almost superfluous to name — 

 everyone knows it. 



Pink and Red Flowers. — Foremost 

 in this color group comes the true moss pink 

 {Phlox subulata). This is a splendid car- 

 peting plant. Better get its improved va- 

 riety rosea, however, because of its pure 

 color and because of the multitude of oth- 

 ers that run into sickly magenta-maroon. 



Before this is to be seen, however, some 

 of the saxifrages send up their brave cluster 

 of fragrant pink flowers. Frequently the 

 flowers open while the snow is yet on the 

 ground. 



All the epimediums that flower in April 

 and May are satisfactory, being dwarf 

 in habit. They come in pink and white. 



From June on until fall, the crown vetch 

 (Coronilla vera) displays its lovely pink 

 flower heads. It is at its best of course in 

 June. 



One almost wonders how the soapwort 

 (Saponaria ocymoides) can bear so many 



The new attractive way of treating a retaining wall. Build it with ample soil pockets and plant rockery-plants in the interstices 



