Dahlia Care
Tuber Storage: If your receive your tubers before it is warm enough to plant, store them in a cool location (40-45F) and check often until you're ready to plant.
Planting Tubers:
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Plant when all danger of frost has passed and soil temps are 60F. This is typically early to mid May in the PNW.
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Select a location that receives full sun and has well draining soil. If you are in an extremely hot climate, partial afternoon shade may be appreciated.
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Dig a 4-6" hole and lay your tuber horizontally with the "eye" up. Provide at least 12-18" spacing between plants.
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It's recommended to place a 24-36" stake into the soil at the time of planting to avoid damaging the tuber. Most dahlias grow tall and require support. You can tie off your plant to the stake as it grows. Tomato cages also work well.
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Slugs love to eat tender dahlia shoots. It's recommended to apply Sluggo or other slug bait, around where the dahlia will emerge.
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Unless you are in a dry climate, or experiencing a drier than normal spring, you won't need to water your dahlia until it's 4-6" tall. Tubers are prone to rot so less is better until the plant begins to establish roots. Once your dahlia is actively growing you can begin to water as needed. Please check your soil and adapt to the temperatures for watering needs.
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When your dahlia has 4-6 sets of leaves, pinch out the center shoot to promote a bushier plant.
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Fertilize as needed throughout the season. Once dahlias begin to form buds use a low nitrogen fertilizer to promote more blooms.
Flower Harvest: Removing spent blooms helps promote more flowers. Dahlias like a deep cut so don't be afraid to cut an 18" stem.
Tuber Harvest: Dahlias will rot in a deep winter freeze or too much standing water. If you decide to harvest and store your tubers in the fall, there are many ways to approach this. I recommend visiting the American Dahlia Society as a great place to learn about digging and storing tubers. https://www.dahlia.org/growing/tubers-2/