Master Gardner Tips: Growing Dahlias

Here is the weekly crop of Master Gardener tips from Nebraska Extension in the Panhandle, relevant to local lawn and garden issues in the High Plains and consistent with research-based recommendations.

Have you considered growing dahlias? The dahlia is a versatile flowering plant, providing a wide array of sizes, forms and colors. Ranging from half-inch pompons to giants, the flower forms vary from daisy-shaped singles to fully double types. Dahlias generally are purchased as tuberous roots which can go directly into the ground in the spring when the ground has warmed and there is little chance of frost. Or if you want early blooms, start the tubers indoors about a month before planting time.

Preparing the dahlia bed: Dahlias should be planted in an airy, sunny place protected from high winds in fertile, well-drained soil. Improve your soil three to four weeks before planting in the spring, by working a 2- to 4-inch layer of organic material into the soil. Add 5-10-5 or 10-10-10 fertilizer at the rate of ¼ pound per 10 square feet when preparing soil. Top dress with this material at the same rate in late July. Rake the fertilizer into the soil and water.

Planting dahlias 101: Buds or “eyes”, from which shoots emerge, are on the crown of the roots. Tuberous roots should be laid on their sides, with buds facing upward, in holes 4 to 7 inches deep and about 2 feet apart. Cover with about 2 inches of soil.  Insert a 4- to 6-foot stake into the ground at the edge of the hole before planting the root to provide support and prevent plant breakage. This extra effort will reward you with vibrant flowers in late July.

Getting big blooms from dahlias: You’ve nurtured your dahlias, and now it’s time to take them to the fair.

To obtain exhibition size blooms, prune the plant to one main stem. Remove all side shoots as they develop, allowing only the terminal flower bud to develop. Remove all other buds.

If you are looking for the greatest number of blooms, pinch out the tip of each plant when it reaches one foot in height. For delayed late summer blooms, pinch new shoots that develop when they reach one foot in length.

Using dahlias as cut flowers: How about brightening someone’s day with a bouquet of dahlias? To use dahlias as cut flowers, cut stems in early morning or late afternoon. Blossoms should be almost fully open when they are cut.

Remove the lower leaves and place the stems in 110-degree Fahrenheit water in a cool, dark location for 24 hours. Recutting the stems each day and placing them in fresh water will help preserve the bouquet. Share your dahlias and bring joy to someone’s day!