THE GARDEN

Otago Daily Times, Issue 26957, 17 December 1948, Page 9

THE GARDEN

Contributed by D. TANNOCK, A.B.S.H.ft.

ANSWERS TO CORRESPONDENTS " Curious,” Milton.—The specimens sent were in a very withered condition, but I was able to identfy No. 2 as Achillea Ptarmica FI. PL, the' double Sneezewort. No 1 looks like Clematic montana, and No. 3 one of the Thalictrums. “ Name of Shrub.”—The name of the shrub sent is Diervilla florida, at one time known as Weigelia rosea. It is a native of China and was introduced to cultivation by Fortune in 1845. J. D. W., Outram. —Daphne odora is one of the most exquisitely perfumed of the evergreen shrubs. It likes a warm, sunny position, where the soil is well drained and a mixture of peat and lime rubble, with ordinary garden soil, should suit it very well. It must have plenty of water during the growing season, and a few stones placed round and under the branches will help to retain moisture in the soil, and assist in the ripening of the wood. It must be well ripened to secure flowers, and a mixed herbaceous border is not a suitable place. I have it growing against a wall of the house facing north, and there it flowers freely every season. C. 8., Broad Bay.—Your walnut leaves are attacked by a fungus, which causes what is known as leaf blotch. Such spots, unless present in large numbers, do little harm, but when an epidemic occurs, the leaves fall early in the season. Spray with Bordeaux mixture, when the leaves are young. Collect and burn the fallen leaves. Lime sulphur 1 in 125 of water can also be used. NATIVE HERBACEOUS PLANTS

By herbaceous plants we mean those which have no woody tissue, such as is found in trees and shrubs. They may be annuals, biennials or perennials, most of the natives being perennials. They are also mainly found above the bush line, where they occur in what is known as alpine and sub-alpine meadows and are found up to the limits of vegetation. Like all alpine and sub-alpine plants they require a lot of moisture at all times, and good drainage, and they thrive mainly in screes or sningle slips where there is little soil but plehty of stones and a little organic matter or peat. They are quite suitable for growing in gardens at lower levels, and though some are quite at home in the ordinary mixed border or in openings in the shrubbery, they are better when grown on toe rock garden or provided with a scree or moraine. This is not difficult to provide if there is a subterranean stream or a system of watering overhead during dry weather. A certain amount of shade (not overhead) is also appreciated by some kinds. A scree even of limited dimensions can accommodate quite a representative collection of toe high mountain species, and it is made by excavating the soil down to an impervious subsoil, or if the subsoil Is shingle or sand a layer of puddled clay can be placed in the bottom. On this a layer of rocks can be placed, then a layer of smaller stones or shingle with a few large rocks sticking up through it, and finished off with a mixture of leafmould or peat one part, and two parts of shingle and sand. The larger rocks on or near the surface will provide shade for the plants which require it, but most can be grown in full sunshine provided there is plenty of moisture below. The Celmislas One of the largest and most Interesting and beautiful types of herbaceous plants are the Celmisias, of which there are at least 55 species, and a number of hybrids and varieties. Not only have they attractive daisy flowers but in a number of cases toe foliage, which is silvery, is also very attractive. Dr Cockayne divided them into three main groups, with a number of sub-groups according to toe manner of growth. Group 1 includes those with large rosettes of leaves, and large or medium flower heads, raised well above toe foliage. These are the easiest to accommodate, and many will survive for years in an ordinary border. The most attractive species is Celmisia coriacea, which has large leaves up to two feet long, the upper sides covered with a silvery pellicule, and beneath silvery tomentose. The flower heads are up to four inches in diameter. Other species suitable for border cultivation are C. Mackaui, C. Hookeri, and C. verbascifolia. A subgroup has leaves like a small speargrass, narrow and dagger-like. The most striking species is C. Armstrongii and C. Petriei and C. Lyaallii are also worth growing. The members of this sub-group are suitable for the rock garden. Gtoup 2 are semi-woody spreading plants, forming large mats or open cushions. The most striking species is C. holoserlcea, which has green leaves and large white daisy flowers. It likes a cool semi-shaded position. Others are C. spectabills, C. prorepens, C. densiflora, C. discolor, C, glandulosa, and C. vernicosa. , , Group 3 are dense cushion plants, very suitable for the scree. The most desirable species are C. argentea, C. sessiliflora C. bellidioides, C. laricifolia, and C. garacelanta. Celmisia vernicosa is the gem of the celmisias. It has dark green glossy leaves, a flower stem one inch to eight inches in height, the. disc florets being bright purple and thd ray ones white or purple. A native of the Auckland and Campbell Islands, it is suitable for the scree. RANUNCULUS FAMILY The next largest and most important group is the ranunculus (buttercup) family, and the most attractive and most desirable of this group is Ranunculus Lyallii, sometimes called the Mount CooK lily, though it is a true buttercup. It has large peltate leaves and white flowers, sometimes semi-double, on stalks two to three feet high, arranged in an open panicle. It is not difficult to cultivate on a raised, well-drained border, but as the old plants die out in time it is advisable to raise a fresh batch from seed every year. Young plants can often be 1 obtained from its native haunts. R. insignis has panicles of up to 40 flowers, their colour being golden yellow. Other species with large flowers are R. Godleyanus, R. nivieola* and R. Munroi. There are a number of dwarf species suitable for a damp place on toe scree. Myosotidium. hortens is sometimes called the Chatham Islands lily, though it belongs to the forget-me-not family. It likes a sandy soil with plenty of seaweed. Aciphylla (spear grasses) are on the whole fearsome plants which can look after themselves- Some send up inflorescences four or more feet in height which are very impressive. Smaller ones suitable for the scree and rock garden are A. Speedeni, A. pinnatifida, and Monroi. Anisotome antipoda and latifolia are noble plants from the sub-Antarctic islands and are suitable for a damp place. Anthropodium cirratum, the rock lily, has long, pale-green leaves and white flowers. Chrysobactrum Rossi has large hyacinthlike leaves and dense racemes of orangecoloured flowers. GENTIANA

There are about 20 species of gentians, but most have white flowers. G. cerina, from the Auckland Islands, has a white corolla striped with reddish purple. Heli-, chrysum bellidioides (false edelweiss) has shivery foliage and close mats of pretty white flowerets. Jovellana Sinclairii has calceolaria-like flowers, suitable for shade. Mazus repens is suitable for a wet place. Leucogens grandiceps, the South Island edelweiss, is a suitable plant for toe scree and is more beautiful than the European one. Ourisia is one of the most beautiful genera of the flora, suitable for the rock garden and the scree. Pratia angulata is a pretty creeping mat plant suitable for 'a moist place on the scree. Wahalenbergia Matthewsii is a pretty little lobelialike plant.