The Home Garden in December

New Zealand Journal of Agriculture, Volume 99, Issue 5, 16 November 1959, Page 473

The Home Garden in December

By

A. G. KENNELLY,

Horticultural Instructor, Department of Agriculture, Dunedin

GROWTH should be vigorous in the well-cared-for garden in December, but of weeds as well as vegetables, so that a sharp hoe should be used regularly between rows. Except in the warmer districts, which have a long comparatively mild period between late autumn and early winter, ground preparation for, or planting out of, winter greens should be high on the list of jobs for late December.

WEEDS in established crops should be eradicated, as they deprive plants of food and moisture and often allow insect pests and diseases to carry over from season to season. Many new weedkillers effective for certain crops have been developed in recent years, but in the home garden hoeing is usually still the most effective means of control. Liquid manure can be applied to most crops lacking plant food, and where necessary watering should be attended to. Water is particularly important to beans, lettuce, and celery. Broad beans attacked by the fungous disease rust should be sprayed with zineb regularly. Rust is readily recognised by its rusty pustules and should not be confused with chocolate spot, a fungous disease which . causes chocolate-coloured blotches on the leaves. Chocolate spot can readily be controlled by copper or thiram sprays.

Celery should be sprayed with captan or a substitute even before leaf spot appears. In the more humid districts potatoes should be sprayed with bordeaux mixture or copper oxychloride or zineb for protection against late blight. The tubers should be kept well covered by moulding the soil to as sharp a ridge as possible. Tall tomatoes need pruning, staking, tying, and, except in some southern districts, spraying with DDT against

caterpillars and with bordeaux mixture or copper oxychloride or suitable Government-certified therapeutant to control fungous disease. Kumara runners should be lifted periodically to prevent them from rooting. If they are lifted regularly, the vines will not mat together and are much easier to turn. In some seasons kumaras will succeed in warm, sheltered areas as far south as Christchurch. Asparagus Too heavy cutting of asparagus will reduce later yields and many beds have been ruined in this way. Harvesting is usually done by cutting the shoots or spears a little below the ground with a sharp knife or asparagus cutter. It is safe to cut half as deep as the top of the crown is below the ground; if the crown is about 4 to 5 in. down, the spears should be cut about 2 in. below the surface. Cutting is usually begun when the spears are 6 to 8 in. above the ground. The spear is first gently pulled to determine its position and, by experience, it can be cut with one thrust without damage to other spears. In loose soil spears can be broken off, but this may damage the crown. The butts of, spears should be trimmed off, though the pieces can be used for flavouring soup. Cutting

should cease early where conditions are dry or if the soil is poor. Onions Where onions have not yet reached maturity weeds not only use up plant food, but when conditions are damp tend to hinder ripening of the bulbs. Though some onion crops are ready for harvesting, those that were planted late or are still growing well should be kept free of weeds and pests and diseases. Parsnips Though parsnips are not usually . lifted until early winter, it is rather late for them to be sown in most southern districts. They can still be sown where, as in northern districts, the autumn is sufficiently long to enable the plant to develop fully before winter stops growth. Hollow Crown and Oxheart are popular varieties. Potatoes December is rather late for planting potatoes, and the success achieved will depend mainly on the district or dryness of the season. It is usually advisable to choose an early or second-early variety for such a late planting. Potatoes need a well drained soil rich in humus. If fertiliser is required, it can be supplied by dusting a mixture of 3 parts of superphosphate and 1 part of sulphate of ammonia in the trench at 6 to 12 oz to every 6 yd of row before planting. Cut or whole tubers can be planted 10 to 16 in. apart in a trench 4 to 5 in. deep taken out with a hoe. For early and very late planting a close spacing can be adopted. The moulding or earthing up of the main potato crop and the digging of the early crop should now be proceeding. The ridges should be finished off to as sharp a point as possible to prevent the spores of potato blight from being washed down by rain to infect the tubers. It is not advisable to earth up when the soil is wet. Blight attack depends largely on the weather. Frequent spells of moist, warm weather are conducive to attack and where the weather favours the disease preventive spraying with bordeaux mixture, copper oxychloride, or zineb is advisable. Potato blight is first seen as irregular, dark brown, water-soaked areas on leaves and stems. The leaves become limp and there may be mildew on the undersides in moist weather. The stems blacken and decay. Tubers should not be lifted when there are blight spots on the leaves, as tubers may become contaminated and later may rot in storage. Infected haulms should be removed at least 10 days before digging. If there is a doubt about the presence of blight on the tubers, they should not be stored.

Potato Scab There are two types of scab which infect potatoes, ordinary scab and powdery scab. They do not differ greatly in appearance, though powdery scab may develop a canker, which is much more serious. Generally scab shows as scabby spots varying from roughened, shallow depressions to corky protrusions. Barriers of cork are laid down by the tuber in an effort to exclude the scab-producing organisms. Scab may reduce the yield by 10 per cent. Control consists of avoiding soils which have recently been heavily limed or to which heavy dressings of organic manure have recently been applied. Heavy dressings of organic matter applied the previous year so that they are thoroughly decomposed are satisfactory. Very acid soils inhibit the development of the parasite, but apart from soil acidity the development of potato scab is influenced by soil moisture and temperature. Its development is usually favoured by conditions where soil moisture is slightly below that giving good growth. Rhubarb Treatment of the main varieties of rhubarb is somewhat similar to that recommended for asparagus. Harvesting of the main crop should not last beyond about eight weeks, though this

depends on the vigour of the plants, the amount of harvesting done, and the moisture content and fertility of the ground. After harvesting has been completed the plants should be given a dressing of farmyard manure, stack bottom, compost, or similar material or a complete fertiliser. Where space permits a good plan is to have several plants of each of three varieties. An early variety which can be forced by covering it early in spring with straw or a good-sized box can be followed, as soon as the early plants require resting, by a main-crop variety which should provide supplies until small fruits are generally available. Finally an ever-bearing variety can be grown .to provide supplies in late autumn and winter. Many varieties of rhubarb in home gardens are affected by virus disease, which may or may not have a serious effect on yield. It usually shows up as light and dark mottling of the leaves, which sometimes become streaked and highly coloured as they die down. Crowns infected by virus should'be destroyed and care should be taken not to spread the disease to healthy plants by handling infected plants and then handling healthy ones Washing of the hands will remove infection. Shallots The harvesting of shallots can be begun as soon as the bulbs are mature

and the roots have started to rot. Proper drying off of the bulbs is important and if the weather is unfavourable, they should be laid under cover in trays in a dry shed. Sweet Corn Sweet corn bears separate male and female flowers, the tassel being the male inflorescence and the ear the female. Pollination normally takes place as soon as the silks appear and development of the cob should be rapid thereafter; the edible stage is usually reached two to four weeks later according to temperature, usually when • the tassel has just withered. Maturity is commonly tested by thumbnail pressure. The young grains are first watery inside, then milky, then doughy, and finally the “dent” stage is reached, when the grains are too hard to be palatable. Cobs should be harvested with a gentle jerk or cut with a sharp knife when the milky part ,of the grain is beginning to thicken but is still milky. In very exposed situations it. is advisable to stake sweet corn, but in most situations earthing up of the stems will provide all the support necessary. Suckers often develop, but do not affect the earliness or number or weight of ears on the stem. Winter Greens Soil and Manure Soil for winter greens should be deep, rich, and well drained and should contain plenty of organic matter. Most members of the cabbage family succeed in a great variety of soils if there is adequate plant food and moisture and drainage is satisfactory. They have very strong root systems, which recover well from injury during transplanting. Heavier soils are preferable for main-crop winter greens, because they retain moisture better and are likely to be richer in plant foods, but light soils are often more suitable for early crops. Rotation of crops is important to cabbage crops, and heavy dressings of organic material such as compost, well rotted stack bottom, and farmyard, stable, or poultry manure are desirable on most soils. Where organic manures are not available a green crop should be dug in, and, except where the soil is very rich, the green crops or organic manure should be supplemented with a fertiliser at 2 to 5 oz per square yard. A fertiliser,having a 1:2 (or 3) : 1 ratio of nitrogen, phosphate, and potash will generally give good results. Side dressings of nitrogenous manures such as nitrate of soda or sulphate of ammonia are often advisable, particularly where the organic matter applied to the soil is strawy rather than sappy or well rotted and when quick, forced growth is required, as in. early spring.

Care should be taken not to apply too much nitrogenous manure in relation to phosphatic and potassic manure or the resulting soft growth will; be easily damaged by frost, insects, and secondary rots. Potash is of particular value for hardening and giving texture to winter-grown brassicas. Where a complete fertiliser is not applied additional . phosphate (best applied by . a dressing of superphosphate) is advisable when farmyard or stable manure is applied, as such materials are low in phosphates. .Though drainage, temperature, moisture, and manure placement are very important, the ultimate weight of the winter greens crop is greatly influenced by the plant food available. Lime Annual. dressings of lime at 2 to 4. oz per square yard are advisable on most soils, though more may be necessary in high-rainfall. districts. Plants such as cabbages and cauliflowers are not especially sensitive to soil acidity, but they grow well in nearly neutral or slightly alkaline soil. Apart from giving the pH level (degree of acidity) of the soil that ensures good growth, liming by making the soil more alkaline tends to inhibit club root. Though popular, the rotation of cabbage or cauliflower and potatoes should be avoided where club root and potato scab are troublesome, as liming inhibits club root but favours the development of potato scab; acid soils tend to inhibit scab, but favour club root. Planting Home gardeners often remove plants from the seedbed and set them out when they are very small. This is advisable only if the conditions are favourable. Plants should be sturdy, close jointed, hardy, and well developed and should be lifted with a fibrous tuft of soil and roots. In the home garden, where there is usually no delay between lifting and setting out the plants, it should not be necessary to puddle the roots in thick . muddy water to keep them moist, as is often done under commercial'conditions. When the plants are lifted the top growth can be dipped in a solution of lindane or nicotine sulphate and DDT if aphids and caterpillars are troublesome. Planting should be done with a trowel, as the plants may not develop properly if the taproot is bent up, as often happens when they are planted with a dibble. If dry, plants in the seedbed should be watered thoroughly the night before they are lifted. Blind plants (those with no growing points) or very weak plants should be discarded. Usually plants with bent or coarse, thick taproots develop better if about 1 in. is cut from the root end. Rows should be 24 to 30 in. apart and

plants 18 to 24 in. apart in the rows, according to the size of the variety. Varieties Choice of varieties of winter cauliflower or broccoli, savoy cabbage, and kale is important. Varieties of winter cauliflower or broccoli can be bought which will mature at different periods so that, if suitable varieties are chosen, a succession of heads for cutting can be had from early autumn until late spring; the latest savoy cabbage is usually mature by August. Kales and sprouting broccolis are most useful during late winter or early spring, when other green crops are often in short supply, but discrimination is needed in choosing the better sorts of kale. Some varieties •of leaf kale have tough leaves with a strong, sometimes rather harsh flavour. The finer-leafed sorts should be grown in the home garden. Asparagus kale and sprouting broccoli are well worth a trial where seed is available, as they are nutritious and some varieties have a delicate flavour if well grown and compare favourably in texture and flavour with the finest of green vegetables. Example of varieties of broccoli which mature successionally are: American No. 1, which produces heads in June and July, American No. 2, heading in August and September, and American No. 3, heading during September and October. Other examples z are Winter Mammoth, maturing in mid winter, Superb Winter White, maturing in June, July, and sometimes in August, Lily White, maturing in July and August, St Valentine, maturing in August and September, and Late White, maturing in spring. The maturity dates are approximate and may vary with strain, district, and season. Non-heading varieties of broccoli include Italian Green Sprouting (Calabrese), Early Purple Sprouting, Late Purple Sprouting, and White Sprouting. Varieties of kale or borecole include fine-leafed sorts which may mature early or late and asparagus kale. Varieties of Brussels sprouts include: Early, Cambridge No. 1 and Harrison’s XXX, both of medium habit with large sprouts; main crop, Evesham’s Special, a tall variety with medium sprouts, Evesham’s Selected, a medium variety with large sprouts, and Covent Garden and Ormskirk Giant, tall varieties with large sprouts; late, Cambridge No. 5 and Scrymger’s Giant, both large varieties with large sprouts. Varieties of savoy cabbage are available to mature from early autumn to about the end of August. A good early variety is Best of All, which can be followed by Drumhead Savoy, Omega, Rearguard, and Ormskirk Late in that order.

SOWING AND PLANTING

Successional Sowings Dwarf beans, beetroot, carrots, celeriac, Chinese cabbages, kohlrabi (where ground is not likely to dry out), lettuces, mustard greens, New Zealand spinach, radishes, silver beet, onions for salads, turnips. Other Sowings j. P.? ™P s ('t seed h as no yet been sown; it is now getting late in southern nets); swedes (sowing can be deferred in warm, dry areas); peas (where soil does not dry out).. Seedings or Tubers Which Can be Set out Celery (self-blanching and ordinary green or white); tomatoes (where plants have not yet been set out and in favourable situations only); lettuce (where conditions are not too hot and dry for transplanting); summer cabbage; cauliflower. Winter greens (except in mild northern districts) such as broccoli or winter cauliflower and savoy cabbage (several varieties of each to ensure succession)Brussels sprouts; kale or borecole; leeks; cabbage for pickling.. A small planting of potatoes can be made, where ground is likely to remain moist enough for good growth; to provide new potatoes in late autumn or early winter. 1