HOW TO BUILD A SMALL ROCK GARDEN. 



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that this Saxifrage, at least in dry, sunny gardens, is not a plant for 

 narrow, sloping cracks between rocks, but thrives best in a large fiat 

 pocket with rich soil, where its offsets have room to grow large. Again, 

 an upright plant like Polemonium mellitum looks its best rising here 

 and there on the north side of the rock garden among quite prostrate 

 plants such as Saxifraga apicv.lata. 



Where there are bold drifts it is much easier to plan good contrasts 

 or harmonies of colour, than where the plants are merely dotted about ; 

 and strong contrasts of colour should be varied by quiet harmonies, or 

 more contrasts of growth or leafage. Thus I found in my own rock 

 garden that an accidental contrast of Lithospermum prostratum with 

 the pink Phlox ' Vivid ' looked well enough because it was mitigated 

 by a mixture of Tanacetum argenteum with its grey leafage. In fact 

 it is possible to combine flowers of almost any colour with good effect 

 if only they are well mixed with quiet-coloured foliage or with white 

 flowers. So where there are bold contrasts of colour it is well to soften 

 them with an intermixture of white-flowered plants, such as the dwarf 

 iVchilleas, and with grey-leaved plants such as the excellent Tanacetum 

 I have just mentioned, or the prostrate Artemisias, or the Aizoon Saxi- 

 frages, or Antennaria, or the woolly thyme. There is particular need 

 of these low-growing, grey-leaved plants on flat parts of the rock 

 garden, which are so apt to look like mere herbaceous borders if not 

 carefully planted. In such flat spaces scale is more important than 

 anywhere else, and any large lowland plant will destroy the whole effect. 

 Often in a rock garden one sees such a flat space, with a few rocks placed 

 at random, covered with plants such as Iceland poppies or Canadian 

 Phlox, or the larger pinks, a space which lacks. both the neatness of a 

 border and the character of a rock garden, and which looks hopelessly 

 ragged and spent by July. Although one may grow no choice plants in 

 such places yet one can exercise much care and skill in planting them, 

 so that they are in character with the rest of the rock garden and never 

 look overgrown or autumnal. In them, as elsewhere, such rocks as 

 there are should be massed, and as large as possible, with broad rock- 

 less spaces in between that may be covered with neat prostrate plants 

 of easy culture. There mix drifts of Viola gracilis with the woolly 

 thyme, keeping the thyme well in bounds with frontiers of rock. That 

 is the place also for large patches of the Gentianella, of Campanula 

 caespitosa mixed with Sedum album, Dry as octopetala mixed with 

 Glohularia cordifolia, and variety of height should be obtained, not by 

 larger lowland plants, but by shrubs such as the smaller Veronicas, 

 Berheris dulcis nana, Iberis ' little gem, ' Ibens correaefolia, and the 

 dwarf Philadelphus, with here and there a larger mass of Santolina 

 mcana or Helianthemum formosum . But the shrubs should not be in 

 too great variety, or the whole effect will be chaotic ; and they must be 

 very carefully placed, and, if necessary, kept well within bounds by 

 tilipping. Those flat spaces are also the places for bulbs, if bulbs are 

 grown in the rock garden. The smaller daffodils and tuhps and the 

 choicer irises may be planted in drifts under a carpet of Seduni dasij- 



