IN THE GARDEN

Dominion, Volume 24, Issue 150, 21 March 1931, Page 26

IN THE GARDEN

Building and Planting a Rockery

By

“Kowhai.”

The first thing to be done when building a rock garden" is to get rid of all weeds from the site, especially twitch, sorrel, and oxalls, for once the rocks are in place it is impossible to cope with them. The rocks to be used should be rough, weatherworn if possible, and of varying sizes. A certain number of big, bold ones are essential.

Start at the bottom of the slope and outline tfce rockery with large rocks. It is not sufficient just to. stand the rocks on the ground. They must be firmly planted to about a quarter of their depth, and should have a slight lean inwards. A point to be remembered is that large rocks must stand on their broadest base. Perched up on end, they look artificial and aro not safe. As soon as the first row is In place, pack behind them good soil, ramming it well Into all crevices. There must be a good depth Of good soil all through the rockery, and good drainage. If there is any likelihood of the soil in the pockets becoming sodden, especially' in winter, at least sjix inches of rubble should be provided before the soil is filled In. /'

From the first t-ow of rocks pockets ate built up, and they must really be built. It Is not sufficient just'to lay'the sjoncs here and there on the' elope or mound of soil. Do not have the pockets all of the same pattern, but irregular of outline, some being large, others small. Big stones should be massed and built up in places to give a bold effect; flat, narrow ones irregularly terraced to give the effect of small ravines. There are infinite possibilities, for the builder to produce a natural-looking miniature hillside. The flat, regular rockery that one sees so often, alas, where the rocks are placed like raisfns on a buu, is to be avoided at all costs. Plenty of crevices and fissures should be left, for many of the alpine treasures are happiest in them, and into these crevices and fissures make sure that you pack good soil containing grit and little bits of rotten rock. Ram It well in when building the pockets, be careful to plant all the stones firmly on their broadest base, always with a slight tilt inwards, and have them •so arranged that soil cannot be washed out of the pockets by heavy rain. Good soil must be rammed firmly behind each stone as building proceeds; and where one'rock'has to be placed upon another there should be a layer of soil between them.

Do not use more stones than are absolutely necessary, even It -you have them to spare. . Keep in; mind always the fact that you are making a home tor plants, not a garden of stones. In time most of them should be hidden by the plants that they are to support. “Then why. use rocks at ail?” I have been asked. “Wouldn’t .the rock plants grow quite well if you just.planted, them air over the slope?” To be sdre they would.'many of theiu. But how flat and uninteresting! How much less; comfortable for the plants, too! No little platforms of deep rich soil for some, no deep, cool fissures-for others to cuddle into, no lovely rock;. faces for traillers to creep over and show off their beauty, no fascinating, irregular steps, or Intriguing little stepping-stone, paths. A .patchwork quilt, in fact. , Once well built and planted, a rocke.ry provides infinite pleasure for its owner. .It is a place to poke about in at all seasons and in all weathers. There is sure to be always something of vital Interest. It is a home for an .jncrcdlble number of little garden friends. When ?it is finished one shoiilq be able to-.walk on all the rocks, in perfect safety. Planting.

Planting is most effective when plants are grouped in bold piasses and drifts of a kind. For bold planting there are helianthemums (sun-roses), in all their lovely colours (sweet-briar, pink, rose, red, tangerine. orange, yellow), catmint, convolvulus mauritanlcus, dlantbuses. hypericums, aubrletias. phlox. subulata, ! dlielranthus (aliioni and alplna). veronicas (prostrata and ruppestris, and the upright spicata). .thrift, sedums, saxifragas, alyssums. lithospermums, ajazanias, ipepembryanthemums. These are hardy sunlovers, and give a feast of brilliant colour. The campanulas are indispensible. They are .a large family, and it is well worth having every member in the rockery. The tiny campanula, pusilia, is a dainty thing for crevices. Used with dwarf pink thrift, and heeria rosea, it Is very delightful for planting in the tiny ravines. ITceria rosea is happiest there- It creeps into nooks and corners, covering stones with a soft green cloak which throughout the summer is studded with big flat magenta flowers. Heeria does not like frost, but grows happily on a sheltered face. •»

Big soft green cushions of mossy saxi-. fragas could not be done without in the ravines, and many of the primulas find a suitable borne in them. Among bulbs for the rockery are many treasures. Anemones, apennina and ncmerOsa, chlonodoxa, crocuses, calchiciums, erythronlums (dog’s tooth violets), iris reticulata, muscarl (grape hyacintihis), narcissus bulbocodium (droop petticoats) mav all be used in patches and drifts. Dwarf irises (pumila) in blue and primrose are lovely, too, and so arc the trailing thymes. The number of rock plants available is verv large. It is best for beginners to start with the hardy ones mentioned. Later, treasures that need Individual attention can be introduced. VEGETABLES As. crops are cleared away a start may be made with trenching and manuring. At this time of year weeds, pea haulm, etc.. may be burled while green, and it is amazing how much can be packed away into quite a small vegetable plot. Weeds, waste rubbish, grass, and hedge clippings are a valuable source of manure, and often the only available one to owners of small town gardens. Good use should be made of everything. Where the ground is vacant, open a wide, deep trench at one end. break up the. soil in the bottom, and then begin packing in all waste material. Tread it firmly down ns each frosh layer is put in. and sprinkle lime freely on it. Hard stems (delphinium, larkspurs, helenium. broad bean) should be cut into short lengths with the seccateurs. When the trench is full, dig the next one. throwing the soil from it on to the green stuff in the first one. and so on until the whole piece of ground has been done. The soil from the first trench will be used to fill in the last one. Leave the surface rough for a time, and sprinkle lime over it. If vegetable crops are not to be sown immediately, make a sowing of blue lupins, to be dug in for green manure later. By doing this, ground that is not to be used for some time is given a chance to become enriched, and all weeds and rubbish are tidily hidden underground where in time they will make valuable manure. Onions. As soon as onions are big enough, they should be bent over at the neck and trodden down. This helps them to ripen off. They should not be left too long in tho ground once they are ripe lest second growth starts and spoils them. Seeds may be sown for a fresh crop, if possible where potatoes have recently been lifted. The ground need not be dug. but just raked level, and the onion plants then get the firm soil that is necessary for them . Any heaps of potato or pea haulms may be burnt on the ground before the onions arc sown, and tiic ashes raked into the soil.