Dahlia Growing Basics

Upon Arrival

Please inspect your tubers. We guarantee dahlia tubers to be the variety ordered with at least one viable eye (growth node). Please email us at goldenacreblooms@gmail.com within 3 days of receipt with any concerns.  Store your tubers in a cool, dark location (40-50 degrees F) until you are ready to plant.

Choose the Right Location

  • Sunlight: Dahlias thrive in full sun, requiring at least 6-8 hours of direct sunlight daily.
  • Soil: Select well-draining, nutrient-rich soil with a pH between 6.0 and 7.5.  Mix in compost or well-rotted manure to enrich the soil.
  • Slugs: Slugs love tender dahlia sprouts. Use good slug control such as Sluggo Plus before you see the first sprouts and slime trails.

Planting Tubers

  • Timing: Plant dahlia tubers in spring after the danger of frost has passed and the soil has reached at least 55 degrees. Do not plant if your soil is extremely saturated or heavy rains are predicted as dahlia tubers are prone to rot before taking root.  Look for a warm, dry weather period.
  • Depth and Spacing: Dig holes six inches deep and spaced 12 inches apart.
  • Initial Feeding: Add to the hole one tablespoon of your preferred slow-release fertilizer and cover with two inches of soil.
  • Plant: Place the tuber horizontally with the "eye" facing up, and cover with 3-4 inches of soil to fill the hole.
  • Label (optional) & Support: Insert a stake or cage at planting time (place eye/sprout closest to the stake) to support tall varieties as they grow, or use horizontal hortnova netting for dahlias rows.  Insert a label of the dahlia variety near the planting hole.

Dahlia Care

  • Watering: Do not water until the first leaves are visible above the soil. Once growth appears, water deeply 2-3 times a week. Avoid overwatering to prevent tuber rot.
  • Fertilizing: Apply a low-nitrogen liquid fertilizer every 3-4 weeks during the growing season.
  • Pinching: Once the plant reaches about 12 inches tall with 3-4 sets of leaves, pinch the center growing tip of the stalk above the top set of leaves.  This will encourage bushier growth and ultimately more blooms!
  • Cutting & deadheading:  When cutting blooms for arrangements, always cut deeply into the plant (think elbow to fingertip deep), sacrificing buds as needed.  This encourages longer stems and more blooms. Remove spent blooms regularly to promote additional buds.
  • Pests: Regularly apply Sluggo Plus during the growing season.  Watch for aphids, slugs, and earwigs. Use natural deterrents or insecticidal soap as needed.
  • Air Flow:  Later in the season, trim up the lower leaf sets of the dahlia plant about 12" to increase air flow at the base and minimize powdery mildew.  

End-of-Season Care & Storage

  • Frost:  Dahlias will continue blooming until your first frost – affectionately referred to as “Frostmas.”  Under proper conditions, your single dahlia tuber will now be a clump of tubers!  Cut your plant down and wait about a week to carefully dig up your tuber clump.
  • Dividing:  You can choose to split your tubers or store them as a clump. If you are new to dahlias, there are many great resources online explaining how to divide tuber clumps.
  • Storage: Dry the tubers (the time varies based on your conditions), then store in a cool, dry location at 40-50 degrees F in your storage medium of choice.  I highly recommend you research the best approach and storage medium based upon where you live.  What works for me in the Pacific Northwest may not be what is best for you in other parts of the U.S.!

 With proper care, dahlias will reward you with an abundance of blooms season after season. Happy gardening and THANK YOU for supporting Golden Acre Blooms!