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Dahlias are rewarding and easy to grow.

Before Planting

Dahlia tubers come in a variety of shapes and sizes. Some may have buds when you receive them, or the buds may still be dormant. Upon receiving your dahlias, open the packages to vent them and place your tubers in a cool, dark place above freezing temperatures until it’s time to plant. A couple of weeks before planting, move your tubers to a warm, bright spot to encourage the tubers to sprout prior to planting.

Planting Time

​Dahlias are sun lovers. Choose a planting site with at least eight hours of direct sun. They also require well-drained soil. If your drainage needs improving, amend your soil with steer manure or sand. Dahlias also need the soil to be warm at planting time. You can get a headstart on the growing season by potting up your dahlias into 2-gallon pots in mid-April and placing the plants in a warm, bright sunny location indoors for a head start. Planting outdoors can be done anytime from the end of April to mid-June.

To plant tubers, dig a hole 6" deep add a small handful of bonemeal into the hole and mix it into the soil. Lay the tubers horizontally in the hole and cover them with soil. It’s advisable to stake plants at planting time and apply a slug bait as soon as you plant. Do not water your tubers until they begin to sprout.

After Planting

After one month, feed monthly with a granular fertilizer that is low in nitrogen and high in phosphorus and potassium. We like to use GardenPRO Bulb food 3-15-6 or Evergro Potato food 6-20-20. During the warm summer months, dahlias need regular deep watering. Remove spent flowers to encourage reblooming. Additional fertilizer applications of GardenPRO Superbloom (10-40-25) every two weeks will also promote better flowering.

After Flowering

As fall approaches, leave your dahlias in the garden until the frost turns the foliage black. A good touch of frost signals to the tuber that it’s time to go to sleep for winter. Dig tubers carefully, cutting off the foliage and leaving only 2" to 3" of the stem. Air dry your tubers in an open box for three days to one week prior to storing. Once the soil around the tubers is dry, gently remove the soil and add vermiculite to surround the tubers. Store the tubers for winter in a cool, dark, frost-free location.

Checks tubers monthly, if they’re beginning to shrivel lightly mist the vermiculite to rehydrate the tubers. If they are getting moldy dust with sulfur.