Cosmos atrosanguineus (Chocolate Scented)

Description

Cosmos atrosanguineus, also known as chocolate cosmos, is a stunning perennial with velvety deep crimson flowers that have a rich chocolate scent. Flowering from June to September, Cosmos atrosanguineus thrives in full sun and well-drained soil. Follow this comprehensive guide to ensure your Cosmos atrosanguineus flourishes and provides months of beautiful blooms.

PLANITNG and AFTERCARE GUIDE

Best Planting Time

• Spring: The ideal time to plant Cosmos atrosanguineus is in spring when the soil has warmed. This allows the roots to establish before the flowering season.
• Early Summer: Planting in early summer is also possible, but regular watering is essential to help the plant settle in.

Site Selection

• Sunlight: Cosmos atrosanguineus thrives in a sunny position, requiring at least 6 hours of direct sunlight per day for optimal flowering.
• Soil: This plant prefers well-drained, moist soil. To improve drainage, incorporate organic matter such as compost or grit, especially if the soil is heavy or clay-based.

Planting Instructions

1. Prepare the Soil: Loosen the soil and mix in compost or well-rotted manure to enrich it.
2. Dig the Hole: Make a hole twice as wide as the root ball and at the same depth.
3. Position the Plant: Place Cosmos atrosanguineus in the hole, ensuring the top of the root ball is level with the soil surface.
4. Backfill and Firm: Gently fill in the hole with soil, pressing lightly to remove air pockets.
5. Water Well: Give the plant a deep watering to help settle the soil around the roots.

Watering Requirements

• During Growth: Cosmos atrosanguineus enjoys consistently moist soil, so water regularly, especially in dry periods. However, avoid waterlogging, as excessive moisture can lead to root rot.
• During Dormancy: Reduce watering in autumn and winter, as the plant enters dormancy. Only water if the soil becomes extremely dry.

Feeding

• Spring: Apply a balanced, slow-release fertiliser to promote strong growth and abundant flowering.
• Mid-Summer: A liquid feed every few weeks will encourage continuous blooming. Avoid excessive nitrogen, as this can lead to more foliage than flowers.

Pruning and Deadheading

• Deadheading: Regularly remove spent flowers to prolong the blooming period and encourage new growth.
• Autumn Pruning: After flowering, cut back the stems to ground level to prepare Cosmos atrosanguineus for winter.

Mulching and Winter Protection

• Mulching in Spring: Apply a layer of mulch around the base of Cosmos atrosanguineus to retain moisture and suppress weeds.
• Winter Care: In colder climates, lift the tubers in autumn, store them in a dry, frost-free place, and replant in spring. If left in the ground, cover with a thick layer of mulch to protect from frost.

Supporting the Plant

• Staking: Cosmos atrosanguineus usually has sturdy stems, but if grown in an exposed area, provide support to prevent wind damage.

Final Tips

Cosmos atrosanguineus is a low-maintenance perennial that adds a unique touch to any garden with its chocolate-scented flowers. By planting in full sun, providing well-drained soil, and following a simple care routine, this beautiful plant will thrive and reward you with striking blooms throughout the summer.

RHS Details

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