Aster 'Duchess Mixed' Seeds

Callistephus chinensis 'Duchess Mixed' is a truly elegant variety that stands apart from standard bedding asters. It produces large, impressive blooms with "incurved" petals that hug the centre of the flower, making them look remarkably like expensive Peonies or Chrysanthemums.

This mix offers a regal palette of colours, including soft pinks, apricots, sky blues, and deep violet-purples. Standing tall on strong, upright stems, they add a touch of formal beauty to the border just as the summer bedding is starting to fade.

Why Your Garden Needs 'Duchess Mixed'

If you love filling your home with flowers, this is one of the most rewarding seeds you can sow. 'Duchess' was bred for the vase. The stems are robust and straight, and the flowers have an incredible vase life, often looking fresh for up to two weeks in water.

I also love them for their timing. They are the stars of the "Late Shift" in the garden. Just as your early summer flowers are finishing, these burst into life in August and September, keeping the garden vibrant right through until the first frosts.

Understanding the Plant: What is a Half-Hardy Annual?

Callistephus is a Half-Hardy Annual.

This means it completes its life cycle in one year (sow, flower, die) and it dislikes the cold. You start the seeds indoors in the warmth of spring, and plant them out only when the weather is officially warm (usually late May or June). They grow rapidly over the summer to put on their spectacular show in autumn.

Growing Guide: How to Sow and Grow

Asters are wonderful to grow, but they do have two specific dislikes: cold soil and slugs.

🌱 Germination:
Sow indoors in March or April. The seeds need warmth (approx 20°C) to germinate. Sow them on the surface of moist compost and cover with a fine sprinkling of vermiculite (they need a little light to wake up). They usually germinate within 10-14 days.

Where to Sow:
I highly recommend starting these indoors rather than direct sowing. Slugs absolutely love baby Aster seedlings, so getting them to a decent size in the safety of a greenhouse or windowsill before planting out gives them the best chance of survival.

Care While Growing:
Plant out in full sun in a sheltered spot. Top Tip: Rotate your Asters! Try not to grow them in the exact same spot two years in a row to prevent soil-borne diseases. Because the 'Duchess' heads are large and heavy, they appreciate a little support from a cane or some netting.

Plant Specifications

Here is a quick reference guide to the key features, helping you decide if these elegant blooms are the right fit for your garden.

My Recommended Garden Companions

If you are growing 'Duchess Mixed' for cutting, they pair wonderfully with other late-summer bloomers. Here are my top picks from the shop:

• 🌸 Cosmos 'Purity': The pure white, daisy-like flowers of 'Purity' provide a fresh, simple contrast to the complex, heavy heads of the Asters. They both flower late into the season together.
• ☁️ Ammi majus (Bishop's Flower): Every good bouquet needs a filler. The white lace of Ammi adds a professional florist's touch to a bunch of Asters, lightening the whole arrangement.

📅 Sowing & Flowering Calendar

Sow indoors in spring. Flowering begins in late summer (August) and continues into autumn.

(↔️ Swipe chart to see all months)