Aster 'Giants of California' Seeds

Callistephus chinensis 'Giants of California' is a spectacular heirloom variety that produces huge, distinctively shaggy blooms. Unlike the neat, rounded heads of other asters, these have long, curling, needle-like petals that give them a wonderful "Ostrich Feather" texture.

They grow on impressive, tall stems (up to 70cm) in a beautiful mix of shades including soft pink, deep rose, violet, dark purple, and white. They bring a relaxed, fluffy elegance to the garden that feels slightly less formal than the 'Duchess' varieties, but just as impactful.

Why Your Garden Needs 'Giants of California'

This is the ultimate variety for the "Cutting Patch." The stems are exceptionally long and sturdy, holding the heavy flower heads high without drooping. A single vase of these shaggy blooms looks like a professional florist's arrangement.

We also value them highly for their timing. They are the stars of the late summer show. When your early annuals are running out of steam in late August and September, these giants are just hitting their stride, keeping the colour going right through until the frosts arrive.

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, provided you protect them when they are young.

🌱 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 benefit from a little light to wake up). They usually germinate within 10-14 days.

Where to Sow:
We highly recommend starting these indoors rather than direct sowing. Slugs absolutely love baby Aster seedlings, so growing them on 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: Try to plant them in a different spot each year (crop rotation) to keep them healthy. Because 'Giants of California' are tall and carry large heads, they benefit from a little support with a cane or some netting to stop them toppling in autumn winds.

Plant Specifications

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

My Recommended Garden Companions

These Asters are tall and textural, so they look wonderful with floaty white companions that help the shaggy blooms stand out. Here are my top picks from the shop:

• 🌸 Cosmos 'Purity': The large, open white faces of 'Purity' look stunning against the needle-like texture of the Asters. Both reach similar heights, creating a lovely swaying display at the back of a border.
• ☁️ Ammi majus (Bishop's Flower): The ultimate florist's filler. The flat white lace of Ammi provides a neutral background that makes the jewel tones of the Asters pop.

📅 Sowing & Flowering Calendar

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

(↔️ Swipe chart to see all months)