Planting Out Dahlias
Remember that the native home of the dahlia is Mexico and that, although many advances have been made in breeding new types, the dahlia is still at its best in a warm, sunny position where it will get plenty of air.
will, however, thrive in a semi-shaded place if it is not in the immediate vicinity of a tree, as the tree will tend to draw the up and make them grow soft, so that they are liable to attacks by . Do not plant them where they will be exposed to cold or frost. Low-lying areas of the garden are likely to suffer most severely from frost because the cold air, which is heavier than warm air, collects in the lowest parts of the garden.
Dahlias prefer a good medium loamy. Although they will thrive in practically any soil which does not dry out rapidly and does not become easily waterlogged. Both these factors can be partially controlled by careful soil preparation. Dahlias are gross feeders, and it is therefore advisable in the autumn to dig into the soil a heavy dressing of decayed farmyard manure, or other , adding a dressing of 4 oz. bone meal to a square yard. Leave the surface of the soil in a rough condition so that the action of frost and the winter weather will make the soil easy to deal with at planting time.
As the soil of every garden differs from that of its neighbours a combination of common sense, observation and experience must guide the gardener in his treatment of his own soil. Some soil may give the best results if lightly forked over in spring when sufficiently dry, and if so, this is a good time to put on a light dressing of an all-round fertilizer, such as one of the specially prepared mixtures made for dahlias or the John Innes base ferti-lizer. Do not exceed the amount which is recommended in the manufacturer’s instructions, for too much fertilizer can kill or injure the plants.
Dahlias look very effective if a variety of forms and colours are planted together, and the bedding types form a colourful display if they are planted in a single colour block.
Plant tubers in the middle of April, as soon as the ground is in a workable condition, and place them in holes 6 in. deep. If a mixture of types is being planted, first insert stakes in the bed so that the layout can be visualized. The stakes should be shorter than the eventual height of the plants and inserted in such a way that the fully grown plants will hide them from view. The spacing between the plants is determined by the height of the dahlias when fully grown. Generally the tall-growing types need to be 3 ft. apart, the medium types 2-½ ft., and the bedding types should be spaced 1-½ ft. each way, to ensure that they give a solid display of colour. Plant any varieties which are to be grown for exhibition in double rows in a separate part of the garden, allowing about 3 ft. between the rows.
Insert the canes or wooden stakes firmly in the ground at one side of the hole so that the tuber can be planted against it, and cover the tuber with fine soil. If the weather has been very wet and so made it difficult to obtain a good tilth, cover in with some well-rotted compost or old potting soil to give the roots a good start.
POT GROWN PLANTS
Plant out rootedin late May or early June when there is no risk of frost. Make sure that the pots are well watered an hour before they are taken to the site, which can be marked out as for tubers. Dig the hole slightly larger than the ball of soil on the plant, and water in each plant by playing a hose or watering-can on the side of the hole, so that the soil is well washed round the roots and the plant is given enough water to start it growing even in a dry period.