Dahlias offer a compact, symmetrical flower and come in a wide range of sizes to suit any gardening situation. These beautiful plants grow from bulbs planted in the spring after danger of frost. Dahlias can be moved but preferably, plants should be allowed to grow and bloom through the season. Moving a growing plant can limit growth and discourage buds and blooms. If you absolutely must move the growing plant, provide the best conditions for transplant to prevent damage to the plant or bulb.
Place the spade shovel 6 inches from the base of the plant. Press down carefully in this position to avoid damaging the bulbs of the plant. Dahlia bulbs are planted relatively deep at 8 to 10 inches.
Work the shovel around the plant at this distance to remove a wedge of soil. Avoid contact between the shovel and bulbs to prevent breakage of the root mass. Perform this task slowly to make sure you aren't hitting the bulbs planted deeply in the soil.
Slip the shovel beneath the loosened plant 10 or more inches below the soil surface. Gently lift the dahlia plant out of the soil with the shovel or grasp the entire bulb mass in both hands to lift it from the soil. Do not break off any bulbs from the root mass.
Choose a new location for the dahlia featuring full sun (6 hours or more per day) and good soil. Select a location featuring well-drained soil since this plant responds poorly to overly wet, soggy soil.
Add peat more to the new planting site by turning over the top 10 inches of soil. Mix peat into the stirred up soil to add organic matter to improve the soil.
Dig the planting hole to a depth of 8 inches. Add additional peat moss by scooping a shovel full into the planting hole.
Position the dahlia plant into the hole to mimic the planting from the previous planting site. Fill in around the bulbs with conditioned soil and press down to firm the soil. Continue adding soil until completely filled in.
Apply a 3- to 4-inch layer of mulch around the base of the plant to promote water retention in the soil. Mulch also helps retain a uniform temperature to the soil that might aid the plant in recovering from a transplant during the major part of the growing season.
Add water to the plant regularly around the base but do not overwater. A thin trickle of water placed close to the plant base will allow water to seep slowly into the soil to reach the bulb mass.