Tips for Growing Dahlias

tips for growing dahlias
tuber sale

Dahlias are among the easiest flowers to grow. All tubers with visible eyes, regardless of size, will produce equally strong plants with prolific blooms.


After Purchasing Your Tubers: Open the bag tops and store in a cool, dark place until planting time. If the tuber has a distinct shoot you could pot it up. Do not place outside yet; but it could be put in a greenhouse.


Location: dahlias grow best in well drained soil protected from the wind. Full sun is ideal, but they will tolerate some shade.


Spacing: space your dahlias according to the size of the blooms: Giants and Mediums should be planted 2’ to 3’ apart. Plant Small, Miniature and Pompons about 2’ apart.


Soil Preparation: about 2 weeks before planting, broadcast 5-10-10 fertilizer over the soil and spade in. Add sand to improve drainage, peat moss or compost to loosen clay soil. Avoid fertilizers high in nitrogen – they promote too much leaf growth and weaken blooms and stems.


Planting: plant after the last frost, usually around May or later. A primary reason for tubers not performing is planting too early. Tubers will not grow in cold, wet ground. This will also cause tubers to rot.

Dig out a 4 to 6 inches deep hole, place in an appropriate stake for the height of the dahlia. Plant the tuber horizontally with the eye about 2 inches away from the stake and pointing up. Cover with soil. Do not water until growth is above the ground. There should be enough moisture in the soil unless we get a long unexpected dry spell. Be watchful for SLUGS, the new tender shoots are on their menu.


For more detailed instructions, the book ‘Growing and Showing Dahlias in Southwestern British Columbia’ is available for purchase from the Vancouver Dahlia Society. Why not attend one of our general meetings where you will learn a wealth of information from experienced growers