How to Care for White Dahlias

Pure white dahlia

Dahlias are prized for their lacy petals and sturdy stems, which make dahlias perfect outdoors in a flower bed or indoors in a cut-flower arrangement. Dahlias are available in a wide range of varieties, colors and styles, and in sizes ranging from tiny 2-inch pom poms to 12-inch giants. White dahlias are especially lovely, whether pure white, creamy ivory flowers or white blooms with a pale pink or lavender blush. Like all dahlias, white dahlias are worth the extra time required to keep them blooming their best.

Things You'll Need

• Dahlia tubers
• Wooden stake
• Soft tie or strips of fabric
• General purpose water-soluble fertilizer
• Organic mulch
• Garden fork
• Cardboard box
• Peat moss or sawdust

Instructions

1. Plant dahlia tubers in full sunlight where the blooms will be protected from strong winds. Choose a well-drained spot and avoid waterlogged soil.

2. Drive a wooden stake into the planting spot before planting the dahlia tuber. If you wait until after the dahlia is planted, you risk damaging the tuber. As the dahlia grows, tie the stem to the stake using soft ties or strips of fabric.

3. Keep the soil evenly moist until the dahlia plant is 10 to 12 inches tall, and then give the plant about one inch of water every week. Water at the base of the plant and avoid wetting the foliage. The white dahlia may need more water during hot, dry weather.

4. Fertilize the white dahlia every month during spring and summer, using a general purpose, water-soluble fertilizer.

5. Spread 2 to 3 inches of organic mulch around the dahlia when the plant reaches 10 to 12 inches tall. Mulch such as pine needles, chopped bark or straw will keep the tubers cool and will conserve moisture.

6. Deadhead, or pinch off white dahlia flowers as they wilt. Deadheading will allow the plant to continue producing more blooms for as long as possible.

7. Dig up the dahlia tubers after the first hard frost in autumn if you live in a climate where winter temperatures fall below 15 degrees F. Cut the foliage down to 2 to 4 inches and lift the tubers from the ground with a garden fork. Brush off excess soil and lay the tubers in a shady spot for about a day, or until they feel dry to the touch. Store the tubers upside down in a box filled with damp peat moss or sawdust, and place the box in a cool, frost-free room until spring.

Tips & Warnings

• Don't remove the foliage from the white dahlias until it wilts and begins to turn brown. The foliage stores energy that the tuber will need to survive the winter and bloom the next season.

References

• Hamilton Dahlia Farm Store: White Dahlias
• Iowa State University: Growing Dahlias