Dahlia Flowers Growing GuideDahlia Flowers Growing Guide
You can start dahlias indoors before planting them out or plant them directly into the open ground after it has warmed up. After all danger of frost is past, plant them full sun and deep, fertile, moist but well-drained soil enriched with plenty of organic matter. Whether plants are already in leaf or not growing, set the roots horizontally 3″ -6″ below the soil surface. If already started, carefully break off the lowest leaves to encourage additional roots to form. Don’t cover un-sprouted tuberous roots completely at planting time–gradually fill in the holes as the plants grow.
After setting out each plant, immediately drive a sturdy stake 6″ from the growing point, especially for tall cultivars. Don’t wait until the plants are up and growing, or you may destroy the tuberous roots. Mulch thickly with pine needles, straw, or compost after plants are at least 6″ tall and the soil is warm. Water often and fertilize liberally throughout the summer with fish emulsion, manure tea, bonemeal, or other fertilizers not excessively high in nitrogen.
When plants are about 6″ -10″ tall, pinch out the center to promote branding and more flowers. You can pinch them again after they put out another 6″ of growth. Tie the shoots to the stake as they grow long enough. When the flower buds reach the size of a pea, remove the side buds to allow the center one to grow as large as possible for its type or leave the side buds on for more but smaller flowers.
- Landscape uses: Many of the shorter and medium-height dahlias make excellent additions to the late-summer and fall border. Taller dahlias can temporarily screen out an unpleasant view. They’re also colorful in front of a tall hedge (leave a few feet between the hedge and the dahlias). Or grow dahlias in a bed by themselves.
- Special hint: Dahlias are hardy in Zones 8-11 if the soil is well-drained and not allowed to freeze; otherwise lift them for winter.
Dahlia Flowers Growing
Pest & disease watch
Handpick slugs and snails when the plants are small, and apply soap sprays to control spider mites in summer. Corn stem borers may attack dahlias, so be on the lookout for wilting shoots and cut them back until you find the borer. Cucumber beetles and grasshoppers relish the flowers; control with pyrethrins. To help keep viruses from spreading; destroy immediately any plants that produce yellow-streaked, twisted leaves or stunted plants.
Dahlia Care and Dahlia Tubers
Place the fork approximately one foot from the stem stub and insert it deep into the soil at least eight inches.
Then gently pry back on the fork to loosen the soil. Repeat this action to encircle the stem stub and loosen the soil. At the last insertion, prying back on the fork should lift the stem stub and the clump of dirt.
Taking hold of the stem stub, gently lift while prying back on the fork until the clump comes free. Lift gently on the clump with one hand, letting it partially rest on the soil.
Using the other hand, carefully remove the soil from the tuber clump. This must be done gently. Many tubers have rather small necks and can be broken or cracked while loosening the soil or carrying the clump to another location.
A tuber with a cracked or broken neck will not grow. Having dug up the dahlia tuber, gently hose it down to remove almost all traces of earth.
It is possible to store the tubers (note that many people refer to a dahlia tuber as a dahlia bulb) immediately they are dug up from the ground – if you want to do it this way, go to the ‘Trim The Tubers’ using the Quick Finder on the left. The best way, however, is to split the dahlia bulb into individual tubers. Splitting the dahlia bulb has the advantage that only the best tubers need to be stored, and individual tubers can be removed from storage if they deteriorate.
Look For The Dahlia ‘Eyes’ or Growing Points
There will be several ‘eyes’ or growing points on the dahlia tuber and it is important to identify these. A tuber will not sprout unless it has at least one “eye.” The eyes are typically found at the top of a tuber on the ridge where the tuber joins the stem. When a tuber is removed from the clump, the ridge containing the eyes must be attached to the tuber. In some cases, this will require taking a piece of the stem as well.
Select Good Tubers
Select the best tuber(s) from your dahlia using the rules below. Not all tubers have “eyes.” It might produce an eye next spring when it is moistened and warmed, then again it may not. Try to save the tubers with visible eyes first. Save the doubtful ones later or discard them. Tubers without eyes may grow roots, as tubers with eyes do, but they will not sprout. The tuber from which the dahlia plant grows (referred to as the “mother” tuber) sometimes rots and dies and sometimes it lives on.
Separate the Tubers
Having selected one or more tubers, separate them from the stem using a sharp knife or large pair of scissors. The aim is to achieve as clean a cut through the stem as possible. Each separated tuber must include a part of the main stem. Remove all excess material from the tuber.
Trim the Tubers
The excess material has been removed which will help prevent rotting during storage. Note that long tubers have been reduced in length using a very sharp knife – in all cases, however, the stem portion at the top of the tuber has not been removed.
Label Each Dahlia Tuber
Each dahlia tuber should now be identified even if they are all the same variety – believe me, you will have forgotten the name by next spring! Common methods are marking the tuber with an indelible pen or placing all tubers of the same variety in a plastic bag which is tagged with their name.
Store The Dahlia Tubers
There are many ways of storing your tubers over winter, you decide which is best for you. The key factors are:
Temperature – keep the tubers in a frost-free environment. A temperature range of 35 – 45 Fahrenheit will suit them fine. In practice, the garage will normally provide the correct environment.
keep the tubers covered away from light. Again, the garage should be suitable.
the tubers must be kept dry, but not allowed to dry out completely. Surrounding them in peat, vermiculite, or sawdust is a good way of achieving this.
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