Getting Started with Dahlia Tubers
Dahlias are one of the most amazing flowers you can grow. There are literally thousands of different varieties to choose from. Yippee— this encourages Dahlia addicts!! (IMO: this is a wonderful addiction!) Dahlia is a genus of tuberous plants that are members of the Asteraceae family. This family grouping of flowers also includes zinnias, daisies, chrysanthemums and sunflowers; no wonder Dahlias are such beloved flowers.
Dahlias are usually an annual plant, unless you are growing them in a climate that does not dip down into the high thirties. Dahlias are usually grown from a tuber, but you can start from dahlias seeds as well. Tubers are clones of the original plant where as seeds will produce a plant that is selected by nature and the plants’ genetic make up.
If you are growing dahlias from tubers here are some easy steps to help you have success:
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Once your tubers arrive store them in a dark cool- high humidity location with some air until they are planted. Keep the tubers from freezing and molding.
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Plant tubers after the risk of frost is over: the soil temperatures are above 55 degrees and in a location that receives at least 6 hours of direct sun. The soil should be fluffy, slightly acidic, organically rich, slightly moist and at the same time be well drained.
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Dig a hole 4-6 inches deep and lay the tuber horizontally in the hole. If the eye on the tuber is visible, face that upward towards the opening of the hole. (IF you don’t see an eye, that’s ok too, don’t panic, it’s still dormant). For taller varieties that reach over three feet, it is best to insert a sturdy tall stake at the time of planting. Pound the stake at least 12” into the soil before placing the tuber into the hole. (Dahlias can also be grown in pots that hold at least five gallons of soil - continue with the instructions below).
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If you are planting other flowers or other dahlias near by, give the dahlia tuber plenty of room to grow once it emerges. It is suggested to give dahlias 12-18” of space per tuber. If you plant too close, this inhibits light and airflow and may lead to poor growing conditions for the dahlia.
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Once the stake and the dahlia tuber have been inserted into the hole, cover the tuber completely with soil and DO NOT WATER (unless the soil is very dry).
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The moisture contained inside the plump, firm tuber along with the general moisture in the soil is enough to make the tuber start growing roots. If you water a tuber that doesn’t have roots there is a good chance it will rot and die.
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Dahlias will break their dormancy at different rates. Some dahlias will begin popping through the soil in as little as two weeks and other varieties can take up to eight weeks to emerge. I promise you it’s worth the wait.
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Dahlias need very little water at the BEGINNING. Once the green stalk of the dahlia is about 6-12” you can begin watering it more regularly. If the soil is extra dry and you have high temperatures while you’re waiting for the tuber to break through the soil, you can give the ground a light sprinkle of water. Remember, too much water without growth will most likely kill your dahlia tuber.
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Now you are on your way to dahlia success and a season of full blooms. Water your dahlia plant throughout the growing season like you would other large annual plants you have in your garden. It's recommended to water 1-2" a week.
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·In the Fall, when frost arrives you can dig your dahlia plant and store the newly made dahlia tubers for next year. See details on dividing and storing tubers.
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Continue reading about Growing and Dividing/Storage