A WALL GARDEN

Otago Daily Times, Issue 22504, 23 February 1935, Page 20

A WALL GARDEN

Although there are some plants that will grow in old walls of any kind, wall gardening is rather a different matter, for it implies the providing of a sufficiency of soil and depth of root-run to suit the choicer alpine and other rockdwelling plants. To secure such essentials to the welfare of crevice growers, the best of walls is one built for soil retention. Erections of this kind are common in gardens where the slopes have had to be levelled up by terracing, and these obviously afford ample roothold behind the stones.

One may build a wall with the sole aim of - creating a congenial home- for fissure plants. In this case, a double wall is desirable, this allowing space for an interior packing of soil. The dimensions of such a structure as this must be decided by circumstances, but one four to five feet wide at the base, slanting to an 18-inch apex, with a height of, say. four to six feet, is suggested. A wall of this kind can make a charming garden feature, serving both as an ornamental divisional fence and a place for suitable plants. Its possession makes it possible to grow an enormous unmber of plants which could never be ' accommodated on the flat.’ > - ■

Aspect blatters little, for there are plants for all nianher of- situations, but it ..is always desirable, in making, a wall, to give- it a-.distinct lean, or batter. Let most-of the blocks of stone-be of good .size,- at least a foot or so’each way. They should- have .'rougish, angular edges, and .may. be granite, _limestone, sandstone, o.r any local material that will build well without looking too monotonously formal. Always build on a sure foundation, let the. blocks of each course bridge the spaces between -those, of the course below, and so on to the top. Always see that stone rests on stone, not on soil, Imt a very little of - the latter may be sprinkled between each. The vertical spaces between the stones in every row may be packed with turfy soil. It is desirablie to give each stone a downward inclination at the back,-so that rain falling on the face of the wall, will flow into it, not off it, and it is essential to ram the soil quite firm - behind ’ the blocks. Any good gritty loam will do for the packing, but just a dash of leafmould and Trioss, peat, mdy be mixed through it if only to retain moisture. No plaster of any kind should be used.,

It is well to put in all larger plants as building proceeds, spreading out' the roots as far back as they will go, but small bits may be easily stuck in afterwards. Then there is seed. Many good wall plants can be grown by simply scattering the seed into the chinks in spring or early autumn. In any .event, it is surprising how quickly, crevice plants will take hold and go ahead. And the wall gardener will find that he is able to grow with success in his vertical rock garden nuhibers of those alpines which arc often a continual anxiety on the, flat. This is because - they enjoy the sharp drainage, and there is no cloying earth round about their necks, no soil splash, but a maximum of sun (or shade), while frosttender plants will enjoy vastly safer conditions.

Most alpine nurserymen offer plants expressly for walls, but the following D i ay j. • as easily-grown subjects distinction and charm. For sunny wallsall asthionemas, Iberis petfaia, and 1. -Little Gem will give every satisfaction, and then there is out old friend nepeta, whose lavender goes so well with the gold of such good wall hypericums as H. cons, reptans, and polyphyllus, Fterocephalus Parnassi and the acantholimons cannot be overlooked, nor can Dianthus caesius, arverneneis, negleetus,. and the little hybrid alpine pinks now being offered. Alyssum saxatile (all varieties) and epinosum, Achillea serbica, argentea, and umbellata will all prove satisfying and easy, and there is no place quite so good as a wall'for the decorative onosmag. Alpine phloxes, Ginum salsolpides, and the golden L. arboreum and flavum are good wall furnishers. and no less can be said of Veronica Guthrieiana, Lyalli, and Dilleni, Gypsophila fratensie, and the pretty little G. cerastioides. In campanulas, C. raddeana, gargaiica, and haylodgensis are to be strongly recommended. Sedum dasypliyllum; faHnosimi, spathulifolmm, stolomferum, and Sieboldi are but a few of the many good stonecrops for this purpose, and there are sempervivums in endless variety. Westerly walls or others not getting all-day sun suit the aubretias, and these revel in a crevice. Arabia, double white and rose, and such delightful little bellflowers as Campanula Miranda, Stands■fieldi, all-the pusilla group, muralis, pulloides,’ pullh, and turbinata also enjoy coolness : with some sun, and they will flower cheerfully-, all summer. The double Cardamine pratensis, such armerias as Vindictive, ccespitosa,' and Laucheana and Erysimum liriifolinm; are first rate. The horseshoe vetch, a yel-low-flowered trailer, Areriaria 1 montana, Hutchinsia alpina, Silene Schafta, Saponaria oeymoides—all prove willing- and aehghtfui. Erinus alpinus is one'of the best pf xyall plants. Orobus vernus and others will do well, ns also the drabas. Among saxifrages almost any of the dwarf and tufty kabschias, the beautiful encrusteds, .including aizoons and cotyledons, must be included, while for rather cooler sides, the dwarfer, more compact mosses of the moscliata class will be perfectly happy. The Vdainty S. umbrosa Elliot’s Variety, primuloides, and geum are also ideal for, partlyshaded' walls.—J,, in. Amateur Gardening.