Getting it to bloom

Why won't my Large Masterwort bloom? (and how to make it flower)

Also called Greater Masterwort, Maxima Masterwort (Astrantia maxima).

More about large masterwort

About Large Masterwort

Astrantia maxima · also called Greater Masterwort, Maxima Masterwort · flowering

Large Masterwort is a robust herbaceous perennial native to the Caucasus, bearing larger-than-average pink pincushion flower heads surrounded by prominent spreading bracts from early to mid-summer. Larger than Astrantia major, it suits shaded woodland gardens and moist borders. Treat as mildly toxic around pets.

Plant type: flowering

Watch for — Drought stress: Leaves wilt and flowers abort if soil dries out; keep mulch topped up and water in dry spells.

The reasons large masterwort isn't blooming

Almost every non-blooming large masterwort traces back to one of these, roughly in order of how common they are:

Too little sun — most of these need full sun (or very bright light) to flower well; shade gives leaves, not blooms.
Too much nitrogen feed, driving lush foliage at the expense of flowers (very common with general or lawn feeds).
The plant has not been deadheaded, so it stops flowering once it sets seed.
Irregular watering — drought or waterlogging at the budding stage makes buds abort.
It is still too young or was checked by a transplant and is rebuilding before flowering.

Feeding large masterwort a high-nitrogen general feed and growing it in too little sun — you get a big leafy plant and almost no flowers.

The fix — how to get large masterwort to flower

Maximise sun. Give large masterwort the sunniest spot you have — for most bedding and fruiting plants, more direct light directly means more flowers.
Switch the feed. Move off high-nitrogen feeds and use a higher-potassium "bloom" or tomato-type feed as it comes into flower.
Deadhead regularly. Remove spent flowers often to keep it producing more rather than stopping to set seed.
Water consistently. Keep moisture even through budding and flowering — drought-then-flood swings make buds drop.

Light and feeding do most of the heavy lifting here. Dial in the spot with the light guide for large masterwort and get the feeding right with the large masterwort fertilising schedule — the wrong feed (too much nitrogen) is one of the most common silent reasons a healthy plant makes leaves instead of flowers.

Bloom season and what to expect

Large Masterwort flowers across its growing season (mostly summer) and, kept fed and deadheaded, can bloom for many weeks or right up to frost.

Post-bloom care so it flowers again

Deadhead, keep feeding lightly, and many will rebloom; collect seed from the best plants at the end of the season if you want to grow them again.

For everything else this plant needs day to day, see the full large masterwort care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Large Masterwort blooming — frequently asked questions

Why won't my large masterwort flower?

Large Masterwort blooms on the season's growth given enough sun, warmth and the right feed — there is no cold or photoperiod trick, just good growing conditions and a bloom-leaning feed. The most common reason it is not happening: Too little sun — most of these need full sun (or very bright light) to flower well; shade gives leaves, not blooms.

How do I make large masterwort bloom?

Give large masterwort the sunniest spot you have — for most bedding and fruiting plants, more direct light directly means more flowers. Move off high-nitrogen feeds and use a higher-potassium "bloom" or tomato-type feed as it comes into flower.

When does large masterwort normally bloom?