FLOWER WALLS

New Zealand Herald, Volume LXXI, Issue 21888, 25 August 1934, Page 8 (Supplement)

FLOWER WALLS

UTILTY AND BEAUTY There are many places where flower walls may be successfully incorporated in the general garden scheme. A change of level justifies the building of a rough stone retaining wall, its purpose to buttress tho soil on some sloping bank, making an ideal place for many rock plants. Grass banks are often difficult to keep in order, and burn brown in summer; in these circumstances, it would be better to transform such places into flower walls. It is never very easy to fit a rock garden into such positions, and the flower wall does not look in the least out of place. The construction of a wall for flower growing does not Dresent any great

difficulties, especially where good stone is available, not only for appearance sake, btft for their stability as well. If properly made dry walling may be carried up to 12ft.- or more. But if n6gligently made a wall only 3ft. high will come down with the first heavy rain. Before commencing the building, prepare a pile of compost of well-rotted manure, and loamy soil. The addition of a few pounds of bonemeal will be an advantage, as the majority of rock plants prefer a slightly alkaline soil. This compost is used in the place of mortar, for filling up the spaces between the stones, and also for filling up the space immediately behind the wall. Use fairly largo stones for tho foundation of the wall, taking care to fill up the interstices with soil. Poor soil may bo used here as the roots of the plants will not reach that far. One of the most important points to remember in building the wall is to tilt each stone slightly backwards, so that the rain falling on the face of the wall may percolate to the roots of the plants; for if this is not carried out the wall will shed rain like a roof. In addition, it will be insecure, and the least thrust from rain will have a tendency to throw the wall down. Do not uso any cement at the top of tho wall, as this prevents moisture penetrating to the roots, and if fairly large stones are used for tho topcourse, coment will be unnecessary. Much of the charm of tho wall comes from cascades of flowers planted at tho top. If possible, place the plants in the wall at the same time as it is built; it is then easier to see that the roots are well covered, and for this

purpose, and for filling in the back of the wall, use the prepared compost. The ideal position for the dry wall is right in the open, exposed to tho sun and air. There may however, be no hesitation in building such a wall in the shade, although a shady dry wall will never produce such a colourful picture as one in the open filled with sun loving plants. When considering the season of bloom, the early part of # the summer presents no difficulties. A wonderful effect can bo created with such varieties as Yellow Alyssum, Perennial Candytuft, Phlox subulata, and Aubrotia. For later bloom Helianthemums, Campanula carpatiea, Linum perenne, Nepeta Mussini,' and several varieties of Sedum and Saxifrage can be added. Although for an enthusiast, it will never take the place of a real rock garden, yet it will provide a place for many plants, which would otherwise be smothered in the borders, or would not be so effectively displayed. Finally, there is massed together a beauty of colour and fragrance, which can rarely be excelled. I

SOIL CONSTITUENTS FOOD FOR PLANTS .All the substances taken up by the plant from the soil must be capable of being dissolved in water, aided by carbonic or other acid. If a portion of dry soil be soaked in pure water for a time the water that is poured off will be found to have altered in character and taste, for the reason that it has taken up from the soil some of the active or soluble substances used as plant food. Perhaps in a fertile soil this will not bo more than two parts in a thousand, so that 998 parts are insoluble in water. But if acids be added to the water with which the soil is soaked a very much larger quantity of plant food will be dissolved out, and this is what occms in plants. The root hairs dissolve out of the soil the active constituents by means of- an acid fluid which permeates the cells of the roots. If, however, the soil from which all the plant food soluble in acids has been removed, be spread out in the air for some weeks and then again be soaked in pure water, it will be found that a small portion of it has again become soluble, and available for plant food. This part was in the first instance in a dormant condition. Henco the advantage of exposing the soil to the air when possible.