Domes of tiny florets sit in a stiff collar of coloured bracts — red, pink, white or light green — held on thin stems above a carpet of deeply lobed leaves. Masterwort (Astrantia) is a star of part-shaded mixed borders, flowering for months on end; give it soil that stays fresh and it will thrive for years.
| Name | Astrantia |
|---|---|
| Family | Apiaceae |
| Type | perennial |
| Height | 1.5→3 feet (0.5→1 meter) |
| Exposure | part shade |
| Soil | fresh and drained |
| Foliage | deciduous |
| Blooming | spring, summer |
Hardy, Astrantia tolerates everything except drought. Soil that stays fresh is ideal for this beautiful perennial.
You can grow astrantia in the sun, as long as the soil stays fresh. Otherwise, it likes partial shade and supports light permanent shade. Plant in the spring, after the last frost. In the south of France, people prefer planting in the fall.
Astrantia is not a plant well suited for pot cultivation.
Indeed, it appreciates a deep and fresh soil, which is often lacking with potted plants.
If you still want to try it, choose a large-sized pot, place it in semi-shade and be rigorous with your watering.
Astrantia self-seeds spontaneously in the garden. To avoid this, just cut off dried flowers as they appear or start wilting. However, we advise against using astrantia seeds for sowing, because they rarely match the beauty of the mother plant.
It is better to divide the clump, as soon as the plant is 3 years old. Proceed in the spring by uprooting the plant with a broadfork. Divide the clump with a spade and replant the pieces in various places. Remember to give a little natural fertilizer at the time of replanting.
Over the first year, you should water regularly to keep the soil fresh. This stops the plant from suffering from drought and promotes good rooting. After that, you only water during dry spells. Each spring, think about adding organic fertilizer, like compost, cut grass, or crushed horn. To keep the soil fresh, don’t hesitate to apply a good layer of organic mulch. Regularly cut off faded flowers, unless you want the plant to self-sow.
Like most perennials, Astrantia deserves trimming once a year. At the end of winter, in early spring, it’s suitable to cut back all the stems to about 4 inches (10cm) from the ground. Vegetation will then start a new season that’ll be rich in flowers.
If you decide to grow Astrantia in a pot, you need to be strict about watering. It’s best to set up an automatic watering system. You can also rely on ollas, which are porous terra cotta waterers. When filled with water, these small containers slowly release the precious liquid, keeping the soil always fresh. Even more so than you would do if planted in the ground, think about enriching your potting soil with fertilizer at the start of blooming and during summer.
Young plants sometimes get nibbled by slugs. You need to protect them using a ring of wood ashes, coffee grounds, or eggshells. Apart from that, this plant is not susceptible to pests and diseases.
Astrantia asks for very little, but each task has its moment in the year. Here is what the plant needs, and when.
| Task | When | What to do |
|---|---|---|
| Planting | Spring, after the last frost | Space plants 12 to 16 in (30 to 40 cm) apart and add two handfuls of compost |
| Watering | Regularly the first year, then dry spells only | Keep the soil fresh so the plant roots well and never suffers drought |
| Feeding | Each spring | Add organic fertilizer: compost, cut grass, or crushed horn |
| Dividing the clump | Spring, from 3 years old | Uproot with a broadfork, split with a spade and replant the pieces |
| Trimming | End of winter, in early spring | Cut back all the stems to about 4 inches (10 cm) from the ground |
| Protecting from slugs | While plants are young | Set a ring of wood ashes, coffee grounds, or eggshells around each plant |
Apart from slugs on young plants, astrantia is not susceptible to pests and diseases.
Don’t trust the delicate appearance of its pretty umbel flowers, Astrantia is a very hardy plant. It easily tolerates temperatures below 5°F (-15°C). You can certainly grow it at high altitudes, in a mountain garden.
Astrantias differ mainly in the colour of their bract collar and, in a few cases, in their foliage. The table below gathers the varieties most often found in garden centres and mainstream catalogues.
| Variety | Bract colour | Foliage | Best use |
|---|---|---|---|
| ‘Sunningdale Variegated’ | Pale pink | Cream and yellow variegated in spring | Grown for foliage interest |
| ‘Roma’ | Soft rose pink | Green, deeply lobed | Long-flowering border, cutting |
| ‘Claret’ | Dark wine red | Green | Borders, cut flowers |
| ‘Shaggy’ | White, green-tipped, long bracts | Green | Part shade, cutting |
| ‘Moulin Rouge’ | Very dark red | Green, dark stems | Borders, cutting |
| ‘Ruby Wedding’ | Ruby red | Green | Borders |
| ‘Hadspen Blood’ | Deep blood red | Dark green | Part-shaded border, cutting |
| ‘Buckland’ | Silvery pink | Green, deeply lobed | Long season in mixed borders |
| ‘Gill Richardson’ | Deep crimson | Green | Borders, cutting |
| ‘Rubra’ | Dark red-pink | Green | Cottage-style borders |
| ‘Primadonna’ | Red-pink, paler tips | Green | Borders, cutting |
The foliage, divided into several lobes, forms a green carpet at the base of the plant. Flowers arise from the clump, atop a thin, erect stem. They have an umbel shape and varied colors: red, pink, white, or light green. They feature a colored bract collar, which highlights the spherical inflorescence.
Strawflower (Xerochrysum bracteatum) has papery bracts that keep their colour and texture as they dry, so bunches hung upside down in a dark, airy spot make lasting dried arrangements.
Astrantia’s domed, bract-collared pincushion umbels attract bees and hoverflies, so planting it near a vegetable plot can support pollinators and aphid-eating hoverfly larvae, though visitor numbers vary with weather and season.
Clump-forming plants expand slowly outward from a central crown instead of sending out runners, so they stay roughly where planted, though whether any particular plant clumps or runs depends on its species.
