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Dahlia planting and growing


Dahlia is an old favorite which, on account of its formal flowers, has been in disfavor for a few years, although it has always held a place in the rural districts. Now, however, with the advent of the cactus and semi-cactus types (or loose-flowered forms), and the improvement of the singles, it again has taken a front rank among late summer flowers, coming in just in advance of the chrysanthemum.

The single varieties may be grown from seed, but the double sorts should be grown from cuttings of young stems or from division of the roots. If cuttings are to be made, it will be necessary to start the roots early, either in a hotbed or house. When the growths have reached 4 or 5 inches, they may be cut from the plant and rooted in sand. Care should be taken to cut just below a joint, as a cutting made between two joints will not form tubers. The most rapid method of propagation of named varieties is to grow from cuttings in this way.

In growing the plants from roots, the best plan is to place the whole root in gentle heat, covering slightly. When the young growth has started, the roots may be taken up, divided, and planted out 3 to 4 feet apart. This plan will insure a plant from each piece of root, whereas if the roots are divided while dormant, there is danger of not having a bud at the end of each piece, in which case no growth will start; the roots are sometimes cut into pieces while dormant, however, but one should be sure that a piece of old stem with bud is on each piece.

One objection to the old dahlia was its lateness of bloom. But by starting the roots early in a frame, or in boxes that are covered at night, the plants may be had in flower several weeks earlier than usual. They may be started in April, or at least three weeks in advance of planting time. Little water will be required till they start.

When they begin shooting up, the plants should have the full sun, and air, on all mild days. They will then make a slow, sturdy growth. All forcing should be avoided. These plants, set out when there is no longer danger of frost, and well watered before completely covering the roots, will grow right on, and often begin blooming in July.

Dormant roots may be set out in May. The roots, unless small, should be divided before planting, as a single strong root is usually better than a whole clump. The roots of all but the Dwarf should be set about 3 feet apart, in rows. In poor soils none but the first class will need stakes.

The dahlia flourishes best in a deep, loose, moist soil; very good results can be had on sandy soil, provided plant-food and moisture are furnished. Clay should be avoided. If the ground is too strong, they will probably bloom too late for the northern latitudes.

If the plants are to be grown without stakes, the center of each plant should be pinched out after making two or three joints. By doing this the lateral branches will start near the ground and be stiff enough to withstand the winds. In most home gardens the plants are allowed to reach their full height, and are tied to stakes if necessary. The tall kinds reach a height of 5 to 8 ft.

Dahlias are very susceptible to frost. After the first frost, lift the roots, let them dry in the sun, shake off the dirt, trim off tops and broken parts, and store them in a cellar, as for potatoes. They may be placed in barrels of sand, if the open cellar is not usable. Cannas may be stored in the same place.

The tree dahlia (D. excelsa, but cultivated as D. arborea) is grown more or less far South and in California. It has not been much improved.