Dahlias add vibrant color and intricate forms to any garden. The ‘Jan van Schaffelaar’ dahlia is prized for its charming appearance and prolific blooming. It is a popular choice for garden beds, borders, and cut flowers, suitable for both novice and experienced cultivators.
Understanding Jan van Schaffelaar Dahlia
The ‘Jan van Schaffelaar’ dahlia is a Pompon Dahlia, known for its perfectly formed, spherical flowers. These blooms, often resembling lollipops, feature ray florets that are blunt or rounded at their tips, with margins spirally arranged and involute for at least 75% of their length. The flowers measure 2 to 3 inches (5 to 7 cm) across.
This variety features vibrant candy-pink flowers, with petals curling inward to create its globe-like form. Against dark green foliage, the pink flowers create a striking contrast. The plant reaches a height of 30 to 40 inches (75 to 100 cm), forming dense, erect tufts that bloom from midsummer to frost.
Planting and Care
Plant ‘Jan van Schaffelaar’ dahlias after the last spring frost, when soil temperatures reach at least 60°F (15.5°C). Choose a location with full sun. The soil should be well-drained, fertile, and rich in organic matter.
Dig a hole for the tubers, placing them horizontally with “eyes” facing upwards, 4 to 6 inches deep. Cover with about 1.5 inches of soil. Space multiple tubers 12 to 18 inches apart.
After planting, do not water until green shoots emerge (this can take two to three weeks) to prevent tuber rot. Once plants are 8 to 12 inches tall, begin watering regularly, providing about an inch of water per week through deep irrigation. Dahlias in containers or hot climates may need more frequent watering.
Ongoing Care
Fertilize at planting with a balanced organic fertilizer. Once plants begin to bloom, switch to a low-nitrogen fertilizer (e.g., 5-10-10) every three to four weeks; excess nitrogen promotes leaves over flowers.
Deadhead spent blooms to encourage continuous flowering.
Pinch the main stem when the plant is 12 to 16 inches tall with at least four sets of leaves. This promotes bushier growth and more flowers.
Stake taller dahlias for support against wind and heavy blooms.
Winterizing Jan van Schaffelaar Dahlia
In colder climates (USDA Hardiness Zones 3-7), ‘Jan van Schaffelaar’ dahlia tubers are not winter hardy and require lifting and storing indoors. The optimal time to dig up tubers is after the first heavy frost, when the foliage has turned black. This indicates the plant has sent its energy back into the tubers. Wait about two weeks after this frost to ensure nutrient translocation.
Cut dahlia stalks to 3 inches above ground. Carefully dig around the plant, avoiding tuber neck damage. Remove soil from lifted tubers; some prefer not to wash, others wash and dry thoroughly.
Tuber Storage
Allow cleaned tubers to air-dry for several days in a cool, well-ventilated area until dry to the touch.
Store dry tubers in a dark, frost-free location with good air circulation and moderate humidity (e.g., a cool basement or garage).
Maintain storage temperature between 40-50°F (4-10°C); too warm causes sprouting, too cold causes freezing damage.
Place tubers in cardboard boxes, paper bags, or plastic bins, covered with moistened sand, peat moss, or vermiculite to prevent desiccation.
Inspect stored tubers monthly for rot or drying, adjusting conditions as needed.