Dahlias will transform the garden in late summer with their vibrant colors and large dramatic blooms. They are part of the Asteraceae family, which also includes sunflowers, artichokes, and lettuce!

The national flower of Mexico, dahlias are native to Central America. They require full sun with well-draining soil. For best results, they will require irrigation. Most dahlias usually need to be watered once a week during the dry summer months, and sometimes twice a week during heat waves.



Dahlias are considered perennials in USDA plant hardiness zones 8 – 10. Outside of this range, dahlias can either be treated as annuals or dug up and stored during the cooler months. In Portland and the surrounding areas, where we are on the edge of the acceptable growing zone, digging up and storing dahlias can extend their life and ensure they do not freeze over the winter.

Dahlias are ready to be dug up when their foliage dies back. By waiting until this point, you allow the plants to gather up and store as much energy as possible before winter. This energy will be crucial when they are replanted in spring and need to send out new growth!

Cut back the foliage and carefully dig up the tubers. Brush off excess dirt and let them dry for several days in a protected area where they have good airflow. If possible, hang them upside down so moisture can leach out of them. The outside should be dry to the touch. Don’t leave them to dry longer than a couple of days because they still need to retain some moisture inside the tuber.

Tubers can be stored in variety of different containers: plastic bins, paper bags, cardboard boxes, etc. Make sure they have space between them and enough room for air circulation. You can use shaved wood, animal bedding, peat moss, or perlite to pack the tubers. Store the packed tubers in a cool, dry, and dark place where they will not freeze over the winter. Remember to occasionally check on them to ensure they are not rotting.

Pro tip: remember to label your tubers when you store them so you know what varieties you own when spring arrives!

In the spring, after the ground warms up and there is no more fear of frost, it is time to replant the tubers! You can divide bunches of tubers before planting and share your growing collection with friends and family!