Dahlia Culture

Soil Preparation	Taking Cuttings	Starting Dahlias Early	Planting Tubers and Plants	Fertilizing and Watering
Topping and Disbudding	Insect Pest Control	Staking and Tying	Mulching and Weeding	Mite Control
Viruses and Diseases	Extending Bloom Life	Hybridizing New Dahlias	Shading Blooms, Umbrellas	Transporting Dahlias
Show Tips, Staging Dahlias	Digging and Storing Tubers	Winter Tuber Storage	Planning Dahlia Garden	Buying Tubers

Garden Location Selection: Dahlias require an area that receives at least half a day of sunlight and has good drainage. Dahlia roots do poorly when they sit in constantly wet soil.

Soil: Prepare your garden area or bed several weeks before planting by spading or tilling the soil. Adding lime (1-2 pounds per dahlia evenly spread over the garden) will lower the acidity if the PH is below 6.0 as measured by a soil test. Dahlias are heavy feeders and a general rule is to add 1 to 2 pounds of 5-10-10 fertilizer per dahlia spread evenly over he garden area and tilled into the soil. A garden of 100 dahlias, in rows 2 feet apart with 4 foot aisles, should receive about 150-200 pounds of 5-10-10. If you have a heavier soil, work in compost or peat moss to lighten and loosen the texture. Additional soil conditioner and fertilizer such as animal manure may be added at this time.

Planting: Before planting, drive 5-7 foot long stakes into the ground to support each dahlia plant. The stakes should be placed approximately 2-3 feet apart with 3-4 feet between rows. After the frost free date, typically mid May, plant you dahlia roots horizontally to a depth of 5 inches with the growing eye pointing upwards about 1-2 inches from the stake. Do not water your newly planted roots unless the soil is extremely dry. Typically, moisture in Spring soils is sufficient for the root. Overly wet conditions can cause the tubers to rot. The growing shoot should start breaking the surface about two weeks after planting. If you are planning to grow your dahlias for exhibition, spread your planting over several weeks - mid to late May and consider getting advice from seasoned growers who exhibit at numerous shows. Dahlias that are grown from plants should not be planted until the end of May, when the danger of frost is over. As a rule, the plants tend to bloom several weeks earlier than dahlias grown from tubers because of the early start.

Watering: There is usually enough moisture in the soil to sustain the initial growing phase. The tuber will begin to form hair roots and the main shoot will break the soil surface after a few weeks in the ground. If the soil becomes dry, a light watering may be necessary at this time. As the plant becomes established and the warmer months arrive, a deep watering twice a week is required. For extremely hot and dry summers such as 1999 and 2005, water more frequently. Once the stem "hardens off" due to the lack of water, it will not enlarge and transport the nutrients for proper plant growth.

Pests: As the growing tips emerge from the soil, they become a favorite food for slugs. Regular application so slug bait around the plant and garden area should minimize the damage. When the plants mature, aphids, earwigs and spider mites also harm them. A weekly spraying program of an all-purpose insecticide such as Ortho Systemic should be used. Be sure to spray under the foliage, as many insects prefer this location. Other methods may also be used to control the insects that might invade your dahlia garden.

Growing: Dahlias should be grown on a single stalk, with multiple shoots removed should they emerge from the ground. The growing tip is removed by pinching out when the plant reaches 6-10" in height or has 5-7 pairs of leaves. This will promote lateral growth and several bloom, one on each of the shoots which grow from the leaf margins. Each lateral will eventually produce a main terminal bud and two adjacent buds. Side dressing each dahlia at this time with a commercial fertilizer will give your plants a boost and enhance your blooms. Another side dressing two weeks later may also be applied. If you are planning to exhibit your blooms, the side buds should be removed by disbudding along with removing laterals which appear one to three leaf pairs below the terminal bud.

Tying the dahlia plants to the stake is required throughout the growing season. The main stalk should be tied when the plant reaches 10-12 inches in height and tied again as the plant grows. As the laterals develop, additional ties are required to support the new growth. The finer points of growing the dahlias to exhibit should be learned from a grower who is skilled in these techniques. A good way to do this is to attend monthly Dahlia Society meetings and ask questions of the members.

If you are not planning to exhibit your blooms and want to maximize the number of blooms and garden splendor, consider letting all the buds flower with no disbudding as is done in the display garden at Elizabeth Park in Hartford. This garden is maintained by members of CDS and is a focal point of the Society. Don't be afraid to experiment, and please enjoy this wonderful and challenging hobby!

Classification: Dahlias are classified according to their size, formation and color. A dahlia over 10" in diameter is designated as AA or Giant, A or Large is 8"-10" in diameter, B or Medium is 6"-8" in diameter, BB or Small is 4"-6" in diameter, M or Miniature is under 4". BA or Ball is over 3.5", MB or Miniature Ball is 2"-3.5", and P or Pompom is under 2". There are also several other classifications such as W or Waterlily, PE or Peony, AN or Anemone, CO or Collarette, S or Single, MS or Mignon Single, O or Orchid and NX or Novelty.

Within the four largest sizes of dahlias there are 5 different types of formations. These are FD or Formal Decorative, ID or Informal Decorative, SC or Semi Cactus, and LC or Lanciniated. The Ball, Miniature Ball and Pompom dahlias have quilled petals which are rounded and short.

Color is the most important attribute of the dahlia with 15 different color classes for each type of dahlia.

Getting Started: Three different ways to grow dahlias: 1. from seed started 6-8 weeks before the last frost, 2. from plants grown from cuttings that were taken from tubers started indoors, and 3. from tubers saved from the previous season. Some growers combine 2 and 3 by starting tubers in flats indoors 3 to 4 weeks before the frost free date and planting the tuber with the plant attached in the same manner as a tuber. Plants and tubers are the only way to grow varieties true to name and color. Tubers and plants can both be purchased from commercial dahlia growers and from your dahlia society.