Cosmos atrosanguineus ‘Eclipse’

Description

Cosmos atrosanguineus ‘Eclipse’ is a striking perennial known for its velvety maroon-red, almost black flowers and its rich chocolate scent. Flowering from June to September, this elegant plant thrives in full sun and moist, well-drained soil. Follow this detailed planting guide to ensure Cosmos atrosanguineus ‘Eclipse’ flourishes in your garden.

PLANTING and AFTERCARE GUIDE

Best Planting Time

• Spring: The ideal time to plant Cosmos atrosanguineus ‘Eclipse’ is in spring when the soil has warmed. This allows the roots to establish before the blooming period begins.
• After Frosts: If planting tubers, wait until the risk of frost has passed to protect new growth from cold damage.

Site Selection

• Sunlight: Cosmos atrosanguineus ‘Eclipse’ thrives in full sun. Choose a planting site that receives at least 6 hours of direct sunlight daily to encourage abundant flowering.
• Soil: Well-drained, nutrient-rich soil is essential. If the soil is heavy or clay-based, amend it with compost or grit to improve drainage. Avoid waterlogged areas, as excess moisture can cause root rot.

Planting Instructions

1. Prepare the Soil: Loosen the soil to a depth of at least 30cm and mix in organic matter, such as compost or well-rotted manure, to improve fertility and drainage.
2. Spacing: Plant Cosmos atrosanguineus ‘Eclipse’ tubers or young plants approximately 30-40cm apart to allow for good air circulation.
3. Depth: If planting tubers, position them 5cm deep with the growing point facing upwards. For potted plants, ensure the top of the root ball is level with the surrounding soil.
4. Watering After Planting: Water thoroughly after planting to help the roots settle.

Watering Requirements

• During Growth: Cosmos atrosanguineus ‘Eclipse’ prefers consistently moist soil but does not tolerate waterlogging. Water deeply when the top layer of soil feels dry.
• During Flowering: Increase watering in dry spells to maintain healthy blooms.
• Winter Dormancy: Reduce watering significantly as the plant enters dormancy, ensuring the soil remains only slightly moist.

Feeding

• Spring: Apply a balanced liquid fertiliser in early spring to encourage strong growth.
• During Flowering: A high-potash feed, such as tomato fertiliser, applied every 2-3 weeks will promote longer-lasting flowers.

Pruning and Deadheading

• Deadheading: Regularly remove faded flowers from Cosmos atrosanguineus ‘Eclipse’ to encourage continuous blooming throughout the season.
• Autumn Care: After flowering, cut back the stems and foliage to ground level to prepare the plant for winter.

Mulching

• Spring: Apply a layer of mulch around the base of the plant in spring to retain moisture and suppress weeds.
• Winter: If growing in the ground, add a thick layer of mulch in winter to insulate the tubers from cold temperatures. Alternatively, lift tubers and store them in a cool, dry place until the following spring.

Container Growing

Cosmos atrosanguineus ‘Eclipse’ is well-suited to containers. Use a high-quality, well-draining compost mix and ensure the pot has adequate drainage holes. Container-grown plants may require more frequent watering and feeding during the growing season.

Final Tips

Cosmos atrosanguineus ‘Eclipse’ is a low-maintenance, long-flowering perennial that adds elegance and fragrance to gardens. By planting it in a sunny, well-drained location and following these care tips, you can enjoy its rich, dark blooms and chocolate scent throughout the summer. Whether in borders, containers, or as a cut flower, Cosmos atrosanguineus ‘Eclipse’ is a stunning addition to any garden.

RHS Details

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