Achillea ptarmica 'Marshmallow' Seeds
If you've ever admired the delicate, airy look of Gypsophila (Baby's Breath) in bouquets but wished for something hardier that comes back year after year, 'Marshmallow' is your perfect match. This charming perennial produces clouds of fully double, pure white blooms that look exactly like tiny marshmallows or popcorn buttons—completely different from the flat, plate-like flowers of standard yarrow.
It's a wonderfully versatile plant that provides that essential 'white noise' in borders, softening bold colours and creating harmony between different planting combinations. As a cut flower, it's absolutely unbeatable—the blooms last beautifully in water and dry perfectly for winter arrangements. Unlike its more temperamental cousin Gypsophila, 'Marshmallow' is tough, reliable, and genuinely easy to grow.
Read More
🌿 Understanding the Plant
Achillea ptarmica is a Hardy Perennial (H7), meaning it's extremely tough and will survive even the coldest British winters.
This is actually a different species from the common yarrow (Achillea millefolium) you might know. In the wild, it's called "Sneezewort" and naturally grows in damp meadows. This heritage means 'Marshmallow' is much more tolerant of moisture than standard yarrow—wonderful news if you have a slightly damper spot in the garden that other plants struggle with.
How It Grows: This plant spreads gently via underground stems called rhizomes, gradually forming lovely generous clumps. After a few years, you'll have plenty of material to divide and share with gardening friends—or expand your own display for free!
🌱 Growing Guide
Achillea is wonderfully easy to grow from seed and often rewards you with flowers in the very first year if you sow early enough.
How to Sow:
Sow indoors from February to April (or in autumn if you prefer). Sprinkle the seeds onto moist compost and don't cover them—they need light to germinate. Keep them somewhere warm (around 18-20°C) and you should see seedlings popping up in 10-14 days.
Where to Plant:
Plant out after the last frost. Unlike other yarrows which insist on dry conditions, ptarmica is quite happy in moisture-retentive soil. It loves full sun but will also tolerate partial shade (though it tends to flop a bit in deep shade).
Keeping It Compact:
Here's a professional florist's trick: in late May (around Chelsea Flower Show time), cut the stems back by about one-third. This is called the "Chelsea Chop," and while it delays flowering by a week or two, it results in bushier plants with stronger stems that won't need staking. Well worth it!
📋 Plant Specifications
| Botanical Name | Achillea ptarmica 'Marshmallow' |
| Common Name | Sneezewort / Pearl Yarrow |
| Plant Type | Hardy Herbaceous Perennial |
| Hardiness | H7 (Very Hardy - survives even the coldest British winters) |
| Light Requirements | Full Sun or Partial Shade ⛅ |
| Height | 60-75cm |
| Spread | 60cm (clump-forming, gradually spreading) |
| Spacing | Plant 45cm apart |
| Flowering Period | June to September |
| Perfect For | ✂️ Cut Flower Filler 🌧️ Moisture-Retentive Soils 🏡 Cottage Gardens 🍂 Dried Arrangements 🦋 Wildlife Gardens |
| Seeds per Packet | Approximately 100 seeds |
🤝 Beautiful Garden Combinations
The frothy white texture of 'Marshmallow' creates gorgeous combinations with bold colours and striking shapes:
- 💙 Larkspur 'Giant Imperial Mix': The contrast of shapes here is simply stunning. The tall, vertical spikes of larkspur in blues, pinks and whites rise beautifully through the soft white cloud of achillea—it's a classic cottage garden combination that never fails to impress.
- 🌸 Zinnias 'Giants of California': The bold, colourful blooms of zinnias look absolutely magnificent when softened by clouds of white achillea. The white acts like a palate cleanser, making the vibrant zinnia colours really pop and preventing the border from looking too busy.
📅 Sowing & Flowering Calendar
Sow indoors in spring or autumn. Flowers from June to September.
💡 Management Tip
This plant spreads via underground rhizomes, which is brilliant for filling gaps quickly. In very rich soil it can be quite vigorous, so lift and divide the clump every 3 years in spring to keep it healthy and under control. This also gives you lots of new plants to use elsewhere!
🏆 Award-Winning Plant
This variety is often sold as 'The Pearl', a cultivar which holds the prestigious RHS Award of Garden Merit. This certification recognises it as a stable, reliable, high-performing plant that's excellent for British gardens.
📖 Want more detailed growing advice?
View our Complete Growing Guide for Achillea ptarmica →
- Regular price
-
£3.25 - Regular price
-
- Sale price
-
£3.25
Couldn't load pickup availability
