The Week In The Garden

Southland Times, Issue 23377, 8 December 1937, Page 12

The Week In The Garden

(By

J. A. McPHERSON)

ANSWER TO CORRESPONDENT J. M. (Gummies Bush).—The best spray for tomatoes under glass is colloidal sulphur. This prevents mildew and leaf spot, two fungoid diseases. Keep an airy and buoyant atmosphere always. To assist the ripening of the berries fork in one ounce of sulphate of potash to the square yard of soil. Potash is absolutely essential to ripening fruits. UNDER GLASS From now onwards artificial heat should not be required in the cool greenhouse. At the moment the average amateur’s house contains pelargoniums and geraniums in full flower. A light buoyant atmosphere suits them best and they must have plenty of light. Shortly, however, atmospheric conditions must be changed, for it will not be long before begonias start to show their first blooms. Both while blooming and in general growth these plants love a cool, moist atmosphere, in fact they demand it, and quickly become stunted if atmospheric moisture is withheld. The plants can be safely syringed overhead each evening, but not sufficient to permit of the water running down into the crowns and starting early basal rot. Floors and benches require heavy damping down two or three times a day and the roof requires to be shaded in order to keep out excessive and scorching sunshine. Seeds of all types of perennial plants can be sown, and when once pricked off into boxes should be stood in cool frames away from scorching sunshine. DAHLIAS The bedding out of the summer display should by now be completed with the exception of setting out the last of the dahlia tubers, more especially those just received from the nurseryman in the form of young plants recently rooted by way of cuttings. This week presents an opportunity of pointing out one or two details essential to the growth of this now very popular flower. In the first place they require ordinary soil and will not tolerate heavy wet soils; in fact they have no objection to very sandy and dry soils provided each plant is given a shovelful of rotted manure under each tuber, and kept well watered throughout the season. I have seen splendid dahlias grown on sandy soil by the above method. Staking should be done early, for there is a tendency for the young shoots to be broken off at the neck during a high wind. For exhibition purposes only one main shoot is permitted to grow from each tuber, and when this is a. foot in height the tip is taken out. This main shoot then branches out into three (sometimes four) strong side shoots, and it is on these that the best blooms are borne. Many and varied are the methods for trapping the great archenemy of the dahlia, the earwig, so we will pass on to a lesser known enemy, but one that has a decided crippling effect on the actual plant growth, thrip. Both the black and colourless thrip play havoc with the young leaves and tender growing tips by sucking the very life blood from the plants.. This results in the leaves assuming a crippled an dwarfed appearance, and no amount of root feeding will enable the plants to outgrow the damage. The pests must first be cleared right off the foliage by spraying (especially on the undersides of the leaves) with warm water to which has been added a teaspoonful of Black-leaf 40 to the gallon. In order that this mixture may adhere to the leaves, ITqp a tablespoon of soft soap to each gallon. (If soft soap is not available it is quite safe to use Lux or Sunlight but never any soaps containing caustic, carbolic, dr other germicides liable to burn tender foliage.) Dahlias appreciate plenty of feeding once they become established, and for show purposes see that the blooms are disbudded by removing from each flower stem the two side buds situated slightly lower down the stem than the main bud. CARNATIONS Carnations are fast making towards their flowering period and must be staked and disbudded. Use inconspicuous stakes if possible; nothing is more unsightly than a carnation flower tied to a thick wooden stake, when a short piece of twisted wire would be much better. The plants will respond to weak applications of liquid manure. Various types of mildews make their appearance from December onwards. One of the commonest is the ordinary rose mildew, and if not checked will cripple the plants and prevent the growth necessary for the second display of bloom. Do not, however, make the mistake of using lime-sulphur while the bushes are at the height of their first blooming, otherwise the blooms will be spoiled. Just after the first blooming is an ideal time, and use the lime-sulphur strictly as directed or even weaker, for should a hot burst of sunshine occur after spraying, there is a chance of leaf scorch. Liver of sulphur (potassium sulphide) is another excellent remedy and is safer to use since it does not burn the foliage in hot sunshine. These two fungicides can also be used for mildew on delphiniums and pansies, in fact wherever mildews make their appearance. THE VEGETABLE GARDEN We are now entering into the drier months of summer and care should be taken to see that on light soils both cauliflowers and lettuce receive copious supplies of water. Dry conditions quickly force both these vegetables to run to seed. Liquid manure along with the general watering will undoubtedly help to produce larger and more succulent hearts. Continue with the earthing up of potatoes and if sufficient spacing has been allowed between the rows, start with the inter-planting of an early batch of savoys that will come into use at the beginning of winter. The savoys will require spraying with arsenate of lead in order to keep diamond-backed moths in check.

Seakale can be given a light dressing of salt. Autumn-sown onions planted out in early spring are making excellent headway this season. A light manuring with nitrate of soda will greatly help to swell the bulbs. This dressing should be given without delay, for if left till later it is liable to interfere with the sound ripening of the bulbs. Continue with the thinning out of root crops and water the permanent plants back into position. Carrots after thinning should be sprayed with a nicotine compound or even thick soap suds in order to keep greenfly in check. I am afraid if dry weather continues, greenfly will prove a real trouble on many vegetable crops, including celery. Cucumbers may be planted on ridges out-of-doors. They will not tolerate cold or draughty situations. Pinch the main tip out of each vegetable marrow plant. It encourages the side growths on which are borne the main batches of marrows.

If desired swede turnips may be sown this month for winter use. Stake tomatoes planted out-of-doors and remove all side shoots.

PLEASING FOLIAGE AND FLOWERS

Plants do not develop specialized organs without some very good reasons, and succulents are no exception to this general rule. Their thick, fleshy stems and leaves are there for a definite purpose, and that to store water during periods of prolonged drought. inis means that most succulent plants come from desert or semi-desert regions, and it is not surprising to find that the majority are not hardy in this country. Nevertheless, there are some outstanding exceptions, and among these are some interesting and beautiful kinds for the garden. The majority of succulents are evergreen, which is a great point in their favour in the gardener’s eyes. Quite a number are worth growing for their foliage effect only, while many flower freely when given the right treatment, and are then most attractive. SUN-LOVING STONECROPS Almost all the sedums or stonecrops are good garden plants. S. spathulifolium atropurpureum is a notable example of the handsome leaved class. Incidentally, the botanical style, which sounds rather fearsome at first hearing, is simply based on the name of a spoon-like implement, or spatula, used by chemists, and it very aptly describes the shape of the leaf, which is fat and round, rather like a little mustard spoon with a tapering base, which suggests the beginning of a handle. These leaves are thick and fleshy, and a good purple colour at all seasons, though this intensifies with hot, sunny weather. S. lydium is another that has the colour of old burnished copper when the weather is droughty. In other respects it is about as distinct as could well be imagined, for it has the narrowest of narrow cylindrical leaves, clustered thickly up short stems, which together form a close carpet of growth. Like S. spathulifolium, it should be planted in poor, well-drained soil, and a hot, sunny position,- if it is to be seen at its best. FOR THE BORDER Most of the sedums are rock plants of more or less prostrate habit, but there are a few which grow to a size that fits them for the herbaceous border, or even for bedding. One of the best of these is S. spectabile. This grows to a height of 18in or so, has thick, rounded grey-green leaves, and close, flatfish heads of pale-pink flowers, which do not commence to open until March, and, in a favourable season, are still quite showy at the end of October. There is an even better variety known as atropurpureum, in which the flowers are a deeper colour. This plant must not be confused with S. maximum atropurpureum, which has rich purplish-crimson foliage, and is well worth a place in the poorest of poor gravelly soils and full sun. The foliage in S. spectabile atropurpureum is just the same greygreen tint as that of the type plant, and the varietal name applies solely to the extra depth of colour in the flowers.

Another immense -family of succulent plants, many of which are hardy, is sempervivum. Until recently, the nomenclature of these was in grave confusion, but now, thanks to the efforts of Mr Lloyd Praeger, light has been thrown into the dim places, and it is possible for the enthusiast to move with greater certainty. Unfortunately, nurserymen’s catalogues are still in a great muddle and the prospective buyer who is really keen on these plants will do well to inspect stock before purchasing. THE COMMON HOUSE LEEK

The best-known species is SemperVivum tectorum, the common house leek. The popular name, or at any rate the first part of it, refers to the frequency with which excellent specimens may be seen firmly established on the roofs of old houses. There they sit, high up on the tiles or slates, with apparently no root-hold at all, except for the dust and dirt which collect around them. All the sempervivums have this curious and accommodating habit of growing with next to no soil at all, and they can often be established quite successfully on the top of flatfish stone in the rock garden, with a thin layer of soil beneath them. But it is not safe to trust choice specimens to this kind of treatment. For them a mixture of soil and old mortar rubble in about equal parts should be prepared, and they should be planted in a depth of at least nine inches of this special compost. There is no harm in placing these pockets on a level with a shelf of rock on to which the plants may scramble at a later date if they so desire; but it would be folly to expose them to Spartan conditions at the outset. One of the most attractive sempervivums, and, incidentally, one of the few that can almost always be purchased true to name, is S. arachnoideum, the cobweb house leek, socalled because its small rosettes of growth are covered with fine white hairs, which do look almost exactly like the work of an industrious spider. It has several good varieties, including one named Laggeri, with rather bigger rosettes than usual, and an extra amount of “cobweb.” Incidentally, S. tectorum is also extremely variable, and seedling forms of it are apt to stray about under various names.—H„ in “Amateur Gardening.” ANEMONE BLANDA From the sunny Isles of Greece and other Levantine shores comes Anemone Blanda, and if ever a plant deserved that specific name it is this adorable little windflower, for pleasing to the point of enchantment it undoubtedly is. This year, the season being mild, it opened its first flowers on January 1, throwing back its brilliant blue rays as if eager to reassure us that long exile from the Balmy Mediterranean will never crab its sweetness nor fail to bring into our northern gardens something of the gladness and romance of its classic home.

The Grecian anemone may not naturalize and spread with the freedom of its sister, the taller and later apennina, but it is by no means shy. Given a bed of gritty soil on the sunny side of some small evergreen, it will steadily increase and at some time between January and March, decided by the weather, break into colour with unfailing trust. Further, from the normal soft rich blue, set off with a golden eye, one may get varieties whose colour equals the blue of Gentian acaulis in intensity; there will be azures of changeful hue, blue-purples, rose-pinks and white. Of this last the lovely variety, scythinica, merits particular mention, for its rays are stained on the reverse with deep violet in telling contrast to the pearly whiteness within.