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dahlia faq

Growing Dahlias FAQ

Questions and answers about dahlias

  • What is the best soil for growing dahlias? The best soil for growing dahlias is a well-draining, fertile soil with a pH level between 6.5 and 7.5. It should be rich in organic matter and have some sand, silt, and clay for adequate drainage and aeration. If your soil does not meet these requirements, you can add amendments such as compost, peat moss, or sand to improve the soil structure.
  • How much sun do dahlias need? Dahlias need full sun for at least six hours a day to thrive. If possible, provide dahlias with morning sun and afternoon shade. In hot climates, afternoon shade is essential to prevent scorching. Too much shade can cause leggy plants and fewer blooms.
  • When should I plant dahlias? The best time to plant dahlias is in spring after the last frost. In colder climates, planting in late summer or early fall is also an option. If planting in late summer or early fall, make sure to mulch heavily to protect the tubers from the cold.
  • How deep should I plant dahlias? Dahlias should be planted 6-8 inches deep. Dig a hole twice as deep as the length of the tuber, and place the tuber in the hole with the stem facing up. Firmly press the soil around the tuber, and water thoroughly.
  • How often should I water dahlias? Dahlias should be watered regularly, especially during dry periods. Aim to keep the soil moist but not soggy. In hot, dry climates, dahlias may need to be watered every day. In cooler climates, they may only need to be watered a few times a week.
  • How do I stake my dahlias? Dahlias should be staked to keep them upright and support the heavy blooms. Stakes should be placed in the ground next to the plant and then tied to the stem at regular intervals. Make sure the ties are loose enough to prevent damage to the plant.
  • How do I fertilize my dahlias? Dahlias should be fertilized every two weeks during the growing season with a balanced fertilizer such as 10-10-10. If the soil is poor, you may want to use a higher nitrogen fertilizer such as 20-10-10. Make sure to follow the directions on the fertilizer package for the application rate.
  • How do I deadhead dahlias? Deadheading, or removing spent blooms, encourages more blooms and keeps the plant looking neat. Use pruning shears to cut off the spent blooms at the base of the stem.
  • How do I protect my dahlias from pests? Dahlias are susceptible to various pests such as aphids, slugs, and snails. To protect your plants, remove any debris or weeds near the plants that could provide shelter for pests. You can also use insecticidal soap or neem oil to control pests.
  • How do I store my dahlias over winter? Dahlias are not cold hardy, so they must be dug up and stored indoors over winter. To store them, dig up the tubers and shake off any excess soil. Cut off the stems and leaves, and store the tubers in a cool, dry, dark place. Make sure to label the tubers so you know which variety is which.

growing dahlias, questions and answers about dahlias