Enjoy Dahlias in Your Garden

Some dahlias can be grown from seeds planted in the earth sprint then placed in pots and planted outdoors after danger of frost is past. These types are available in nurseries and garden centers. Popular bedding types of dahlias include Unwins Dwarf and Border Jewels. These bedding types have semi double to double flowers on bushy compact plants growing 18 to 24 inches tall. The short flower stems on most of them do not make them satisfactory flowers for cutting.

The most spectacular blooms are available on varieties which are grown from root divisions. The tuberous roots of dahlias can be separated from the clump in which they grew. Each root develops into a new plant if the root division contains at least one eye. Unlike a potato, which is a structure that has eyes scattered over the surface, the dahlia is a true root which has eyes only on the portion where it joins the stem. Some dahlias have long roots with a thinner area or "neck" between the main root and stem.

Care must be taken in handling these roots so this thin area is not broken. Among the most spectacular of the large flowered dahlias are the cactus and decorative types. Cactus dahlias are those in which the petals curl back, giving each one a sharp, pointed appearance. Incurved cactus dahlias are those in which all the petals curve toward the viewer, while straight cactus have stiff petals that radiate out from the center like the sun's rays. Semi-cactus dahlias have curved petals, but in a looser arrangement, making them closer in appearance to the informal decorative types that have petals that are not curved but arranged loosely.

The formal decorative types have exactly arranged petals. The best forms of these types are fully double and may be 8 or more inches in diameter. For development of the largest flowers, allow only one bud to develop on each shoot. These beautiful large-flowering types are not very desirable landscape plants and should be grown primarily for their flowers. The plants grow very tall, often reaching a height of 6 or 8 feet. They are relatively weak stemmed, and therefore must be staked.

Stakes should be set in place at the same time the root are planted. Dahlias need a lot of sunlight and a deep, rich toll with good drainage. Work the planting area to a depth of about 12 inches. The roots should be placed in a horizontal position, about 4 inches deep in heavy soils or about 6 inches deep in sand soils. Cover the roots with only about 2 inches of soil and as the shoots grow, gradually fill in the hole. Tall growing varieties should be spaced about 3 feet apart in the rows with about 4 feet between rows.

Dahlias are heavy feeders and need adequate fertilization at planting and during the summer. Add organic matter when preparing the soil. A 2 to 4 inch layer of aged manure dug into the soil will be beneficial, although compost or peat moss might also be used. A complete fertilizer should be added at planting time. Apply about one-fourth pound of a complete fertilizer such as a 12-12-12 to each 10 square feet of garden area. This same amount might again be a aided to the surface in July. As the plants begin to grow, allow only one strong, healthy shoot to develop from each root Remove all other shoots.

http://en.wikipedia.org/wiki/Dahlia