Illustration
Masterwort
Astrantia major
Also called greater masterwort, great masterwort and melancholy gentleman
Also comes in pink and red.
Masterwort blooms from May through July.
Months here are Northern Hemisphere months; in the Southern Hemisphere, shift them by six months.
Growing Masterwort
Plant it in part shade. It prefers moderate water. It is hardy in USDA zones 4–7. Expect it to reach about 24 in tall and 20 in wide at maturity, in roughly 2 years (a house reading).
Pets
- Not yet checked for pets.
Lists differ and none is complete. If a pet eats a plant and seems unwell, call a veterinarian or a pet poison helpline.
No toxicity note is on file for Masterwort. That is not a clearance: check its safety for people and pets before planting.
What was checked
Nine facts were checked against named botanical sources, each recorded beside the sources that carried it: mature height and spread, hardiness zones, sun, water, bloom months and color, the trait tags, and years to mature size, which rests on a recorded house rule where no publisher states one and is marked so. Soil, diseases, pests, toxicity and the plant's own names have not yet been read for this plant, and its trait tags are the ones a feature uses rather than every word a page prints. Each fact above carries its own mark. The planting, spacing and size sections are derived from these checked facts by a fixed rule, not checked separately, and the plant type is the library's own classification.
When to plant Masterwort
Plant Masterwort in early spring as soon as the soil is workable, or in early fall at least six weeks before your first frost, so roots establish in cool weather. In zone 5, the middle of its hardy zones 4 to 7, spring means April to June and fall means August or September. Once settled, it blooms from May to July.
Month-by-month timing for your zone is on the planting calendar; if you garden near zone 5, the middle of this plant's hardy range, start with zone 5 in April. Derived from the plant's category, zones and bloom months plus typical zone frost dates, not checked separately.
How big does Masterwort get?
24 intall5 ft 7 inan adult20 inwideSee Masterwort in a garden plan: the planner shows it in 3D beside everything else you add, growing toward this size over the years.
How far apart to plant Masterwort
Derived from the mature spread above by a fixed rule, not checked separately: spacing is the spread, center to center.
Space Masterwort about 20 in apart, center to center, so each plant has room to reach its full width.
Add Masterwort to a garden plan and the planner draws it at its full width, so you see the spacing before you buy.
Where these facts come from
Masterwort's height, spread, hardiness zones, sun, water, bloom months and color and trait tags were checked against 7 published sources on October 19, 2026. Each one is linked below with every fact it carried, which can include a fact this page still marks as not yet checked, because a source carrying a value is not the same as the value being held to the standard. Facts not in that list, and the planting, spacing and size sections, are not covered by these sources.
- Missouri Botanical Gardenheight, spread, hardiness zones, sun, water, bloom months and color and trait tags
- Perennials.com (Heritage Perennials)Heritage Perennials / Valleybrookheight, spread, hardiness zones, water, bloom months and color and trait tags
- burncoose.co.ukBurncoose Nurseriesheight, spread, water, bloom months and color and trait tags
- jparkers.co.ukJ. Parker'sheight, spread, sun, water and bloom months and color
- University of Wisconsin HorticultureUniversity of Wisconsin-Madison Extensionhardiness zones, sun, water, bloom months and color and trait tags
- hoohouse.co.ukHoo House Nurseryheight, spread, bloom months and color and trait tags
- RHSRoyal Horticultural Societyheight, water and bloom months and color
How the checking works, and what each standard covers, is on the verified plants page.
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Design a garden with this
Drop this plant onto a 3D plan, see how it fills in, and watch your whole garden bloom across the year.