Dahlia Collarette 'Rhubarb and Custard'

PreOrder Shipping Begins March 15, 2026!

Dahlia Collarette ‘Rhubarb and Custard’ is an irresistibly cheerful collarette dahlia, instantly recognizable for its playful contrast and delectable color pairing. Each flower features a single row of smooth, slightly pointed outer petals in rich cranberry red, reminiscent of stewed rhubarb. These petals often show subtle variations of magenta or cherry tones, giving each bloom a dynamic, painterly quality.

Planting Tips for Dahlia Collarette ‘Rhubarb and Custard’

Site Selection

• Plant in full sun, with at least 6 to 8 hours of direct sunlight.

• A location with good airflow helps prevent powdery mildew and keeps plants dry after rain.

Soil Preparation

• Use loose, well-draining soil enriched with compost or well-rotted manure.

• Dahlias thrive best in soil with a pH between 6.2 and 7.0.

• Avoid clay-heavy or waterlogged areas, which can cause tuber rot.

Planting Depth and Spacing

• Plant after the danger of frost has passed and soil warms to about 60°F.

• Dig a hole 4 to 6 inches deep.

• Lay the tuber horizontally with the eye facing upward.

• Cover lightly and avoid heavy watering until stems emerge.

• Space tubers 18 to 24 inches apart to allow room for branching.

Support

• Collarette dahlias are moderate in height, but giving them a small stake or light support helps keep stems upright in wind or rain.

Watering

• After planting, water sparingly until green shoots appear.

• Once plants are established, water deeply 2 to 3 times per week.

• Aim for consistent moisture but avoid saturated soil.

Feeding

• Apply a low-nitrogen fertilizer such as 5-10-10 or 10-20-20 once plants reach 12 inches tall.

• Continue feeding every 3 to 4 weeks throughout the growing season.

Maintenance

• Pinch out the growing tip when the plant reaches 12–16 inches tall to encourage bushiness and more blooms.

• Deadhead spent flowers regularly to prolong blooming.

• Mulch lightly to maintain soil moisture, being careful not to cover the stem base.

End-of-Season Care

• In colder climates, dig and lift tubers after the first frost. Label, dry, and store them in a cool, dark, frost-free place.

• In mild regions, tubers may overwinter in the ground with a protective mulch layer.