Successional Planting in the Flower Borders

New Zealand Journal of Agriculture, Volume 84, Issue 4, 15 April 1952, Page 341

Successional Planting in the Flower Borders

THE PRECEPT "give young plants ample ’ room in which to develop" should be borne in mind by the gardener who desires a satisfactory succession of blooms. Attention to the points made in this article for the flower gardener by the Horticulture Division will enable successional plantings to be made successfully, avoid wastage and loss of young plants, and ensure, that the border makes a continuous display and that plenty of young plants are always coming into flower in the border as the old ones fade.

IF CERTAIN basic principles are followed, the flower border in the home garden can be made much more colourful and effective. The need of never missing a sowing or planting date cannot be over-stressed, but there is certain to be a period when the borders are out of flowers and dull if planting a new batch of plants is delayed until the borders look shabby. Successional planting is needed to keep flower borders continuously bright.

Importance of Light to Young Plants

However, successional planting does not mean merely setting out young plants between the old ones; it is not quite as easy as that, because most flants need moisture at their roots and ight for their leaves in order to grow. Some plants, such as the ferns, can grow where there is relatively little light, but nearly all the plants which are grown in the flower border need direct sunshine on their leaves for at least part of the day if they are to thrive. Leaves that are shaded from the direct rays of the sun turn pale green or yellow (etiolated), often become thin and weakly, and can neither do their work of manufacturing sugars and starches for the plant nor resist the attacks of diseases.

In Nature, and especially in the New Zealand bush, many plants are able to exist in shady places on the forest floor when young and send out stems which struggle up into the light among the tree tops. Once their heads are in the light these plants thrive and develop to maturity. Unfortunately, most garden flowers have none of this ability. Unless they have light from their early, seedling stages they become spindly and weak and often die. Even those which may survive and .ultimately grow through neighbouring plants into the light are usually short lived and incapable of producing a worthwhile display of flowers. Water Equally Important A constant supply of moisture to the roots is just as important to young plants as the supply of light. Plants cannot grow without enough moisture, lack of water first causing growth to cease and then leaves and stems to wilt. Plants can recover from a certain degree of wilting, but there comes a point when wilting is so severe that the tissues cannot recover and the plant dies.

As • the plant’s water supply is all taken up from the soil by its young roots, a well-developed root system is ' needed to reach out and use the available water in the soil. A plant with i small or mutilated roots is ill equipped to grow in a dry soil where a plant ; w h longer, deeper, and more numer- . us roots probably could grow quite Thus young plants set out among older ones will be poorly equipped to : use such water as the soil may still contain, especially if they are planted in summer and autumn, when the soil moisture has been drawn on heavily ,in the + b ? r< J er - Fr . that reason it is important to water plants m and, if the soil is dry when they are planted, to continue to water them until they have developed good root systems. Successful Successions! Planting i lam my There are thus two reasons why : young plants “just popped in” between older ones are often a total loss, ’ disappearing from sight and mind as ; they are overshadowed by their more 1 strongly growing neighbours, which

rob their leaves of light and their roots of moisture. No wonder there is little left of the young plants, on which much care may have been lavished, when the overgrown old plants are finally pulled out. To establish new plants successfully in T ° a fl ower j n g border it is always worth while to raise and grow them elsewhere to fairly large size so that they are well enough developed when planted to compete with neighbours for light and soil moisture. That emphasises the advantage of raising successions of plants in boxes and pots for planting out in the border. Alternatively, if seeds are sown or small seedlings planted out in the border, they must be put only in fairly extensive gaps where they will not be overshadowed by the tops or robbed of moisture by the roots of established neighbours. Coupled with this replanting policy should be ruthless tearing out of old annuals when they have passed their peak, and perennials such as marguerites and hybrid wallflowers should be cut back hard, even though they still have quite a number of flowers, to leave room for the proper development of the new plants;

Annuals sown earlier for spring flowering should be thinned to an inch or two apart as soon as they can be handled. Further thinning is necessary as the plants become larger, until they are finally thinned to 8 or 9in. apart by the time they are in flower. Annuals that have been raised in boxes from seed, or self-sown seedlings lifted from the borders, can still be planted out in vacant spaces in the borders in very mild districts, but elsewhere these seedlings are probably better not planted out until the end of winter. Cinerarias should be inspected from time to time. The “woolly caterpillars that can devastate cinerarias later in Jhe season can usually be kept down by hand picking at this time, but spraying with D.D.T. in spring and early summer is well worth while. Chrysanthemums are usually left in the border from year to year in the milder districts, but where sharp frosts are experienced it is safer to lift the stools in autumn, label them, and plant them in a cold frame for the winter. Little water or attention need be given them through the winter,,but these plants will provide a good supply of cuttings when they are required for propagation later. Cuttings will form new roots only if a continuous supply of soil air reaches the cut surfaces, where the new roots will appear. Success with cuttings depends on, among other things, the texture of the soil in which they are put to root. Silty soils, such as those in many New Zealand gardens, run together when watered and form a crust when they dry. The more often they are watered the tighter this crust becomes and the more difficult it is for air to pass through it. Cuttings in a pot, box, or frame must be damped down often until they root, and they root badly in a silty soil because the supply of air to their roots is insufficient. Now is the time, when the cold frame is more or less empty, to make sure that the texture of the soil in it is suitable for propagation. A liberal addition of

coarse, gritty sand will do much to open the texture of the soil, prevent it from caking when watered, and so ensure a good supply of air to the bases of cuttings to be propagated next season. Dahlias left in the ground the Dahlias left m the ground from the previous year produce the earnest blooms, but they cannot be left, out - doors safely in districts where winters are hard. Except in the mildest distr j cts the roots are better lifted, dried o ff an d stored for the winter in a place where they will be protected fro^m frost They do not require a W arm place, temperatures between 35 and 40 , degrees F. being satisfactory, In re i a tively mild districts the roots can be kept beneath an evergreen hedge if shed storage is not available, In mild districts where dahlia roots are cus t O marily left in the ground through winter it is advisable to lift them in late winter at least every 3 years and divide the old roots or rep ] an t single tubers taken from the outside of the old clumps, making sure that each tuber has at least one bud on jt s neck Dead flower heads _ should be removed regularly even in winter if

the borders are to be kept in flower for as long as possible. They should always be cut off with a knife or scissors or pinched off with the thumb nail, and never pulled off, as pulling is likely to wrench the roots and may even result in some of the annuals being pulled out of the ground. Deep digging does more than anything else to encourage the large, deep root systems which are necessary if plants are to grow well. Plants with shallow roots are sensitive to dry conditions when the surface soil dries out, whereas deep soils remain moist for much longer and roots can draw a constant supply of moisture from the deeper layers. The mixed border gives less opportunity for deep digging than does the vegetable garden, but every opportunity should be taken of digging the borders, even though only small areas can be dug at a time. Digging in autumn is especially beneficial, as rain soaks more readily into soil that has . been broken up; much badly needed moisture runs off the surface instead of soaking into the soil if the flower border is left with a hard surface through winter. All hard surfaces should now be pricked lightly with a fork even if the ground is occupied and cannot be dug over. The aim should be never to let the ground become hard, but to loosen the surface whenever it shows signs of caking to make sure that rain, can soak in instead of running off. Herbaceous plants in the borders should continue to be lifted, divided, and replanted after the digging ana manuring of the site. Planting time for most trees, shrubs, and herbaceous plants extends from about May to early October. Advantages of autumn planting are that the soil is still relatively warm after summer and plants usually form new roots quickly. The cool, moist conditions of winter are least trying to newly planted stock, but winter storms are likely to rock shrubs and trees planted in autumn, as they will not have had time to produce new anchorage roots, and a very wet spell in winter will often kill newly planted stock outright if the soil is poorly drained and becomes waterlogged. Spring planting is less likely to result in trouble from waterlogging by heavy winter rains, but the plants will have less time in which to form deep root systems before the arrival of hot, dry summer weather. Spring planting is best if the soil tends to be wet in winter.

Pot plants should be trained as bushy specimens and not be allowed to become . leggy. . Young fuchsias, balsams, and . geraniums potted up as rooted cuttings to flower next year should be pinched several, times, as they .grow to cause them. to. produce well-branched plants. . Pinching means the removal of the tip of a shoot while it is still soft enough to be pinched off between the, finger and thumb nail.

Sweet peas should be given as long a growing season as possible. In early districts where the site will be ready for planting by July or August seeds should be sown in May in pots or boxes in a cold frame. They should be given quite hardy conditions and' need the protection of the frame light only in really cold weather. Seeds are sown IJin. apart and lin. deep. v

Eelworm often affects chrysanthemum plants, resulting in the leaves drying prematurely and shrivelling. This pest can be controlled properly only by hot-water treatment of the stools in winter and planting them in sterilised soil. Cuttings from plants treated in this way will be free from eelworm . and, if planted in soil not infested with eelworms, will grow into healthy plants retaining all their leaves to the ground.

Mildew on a variety of ornamental garden plants can best be controlled by a sulphur fungicide. The most effective method is to use a liquid spray such as lime sulphur, colloidal sulphur, or, best of all* a combination of the two, but . the use of sulphur sprays is limited seriously in the flower garden by the fact that all these liquids discolour paint work and cannot be used safely near the house. A fairly satisfactory method of combating all the common mildew diseases on flowering plants is to use sulphur in the form of a dust— flowers of sulphur or a proprietary sulphur dust. Dusts are not as efficient as liquid sprays, but are reasonably effective if applied very uniformly, preferably in the early morning when the plants are still damp with dew. One method of application is to put the dust in a piece of cheese-cloth, tie the bundle to a stick, and shake the stick or tap it with another to drive off a small cloud of the dust. However, that is a wasteful method, and every home gardener will find a hand duster a good investment.

Spotted wilt virus disease of tomatoes is carried over from one year

to the next on a variety of plants, especially dahlias, lettuces, ■ Iceland poppies, and nasturtiums. Dahlia roots marked earlier as virus infected, and any of the plants named which show spots on the leaves or are stunted, malformed, or in any way abnormal, should be dug out and burnt. Rigorous killing of infected plants that are carrying over the disease from year to year gives some hope of reducing losses in next season’s tomatoes.

“Shih Chin” or “Ten Best Parts” A Special Chinese Dish

rr WO very special Chinese dishes are made from titbits of ten different vegetables or meats, carefully cooked and seasoned. In China the “ten best parts” • (“shih chin”) would include some of the ; rarest Chinese delicacies; the following recipes have been simplified to include only ingredients obtainable in New Zealand:— . Ten Best Parts Vegetable 1 small cauliflower 2 tablespoons of stock 2or 3 pieces of celery 3oz. of butter, 1 cabbage ■ heart or 2 dripping, or lard or 3 sprouts 1 tablespoon of soya2oz. of shelled broad bean sauce or a beans teaspoon of meat or 2oz. of celeriac vegetable extract 2oz. of bamboo shoots dissolved in hot (if obtainable) water ■ 2or 3 sticks of - J . teaspoon of ve tsin asparagus , (aromatic flavourjib. of mushrooms Ing which can be 2 or 3 spring onions omitted) 2 tablespoons of green Salt peas Cornflour to thicken Chop all the vegetables fairly finely. Heat the fat in a heavy pan and fry the cauliflower, celery, beans, and celeriac for 5 minutes, stirring them all the time. Add the rest. of the vegetables, the soya-bean sauce, and

salt to taste and cook the mixture for 5 more minutes. Add the stock and the ve tsin, and when the mixture is boiling thicken it with a little cornflour mixed with cold water.' Cook it for another minute or two and serve it with steamed rice. Ten Best Parts Meat 1 chicken liver 2oz. of mushrooms 2oz. of ham 1 slice of green 2oz. of cod ginger root 1 leg of chicken, 3oz. of butter,. lard, cooked or dripping 2oz. of fresh shrimps 1 tablespoon of soyaloz. of fresh lobster, : bean sauce , crayfish, or crab 2 tablespoons of stock 1 tablespoon of green Salt peas Cornflour 2 spring onions Chop all the ingredients fairly, finely. Heat the fat and fry the liver, ham, and cod for 4 to 5 minutes. Add the rest of the ingredients and fry them for another 5 minutes. Thicken the mixture with cornflour and cook it for another 2 minutes. Serve it with steamed rice and more vegetables.

—DOROTHY JOHNSON,

formerly Rural Sociologist, Department of Agriculture, Christchurch