Getting it to bloom

Why won't my Korean Angelica bloom? (and how to make it flower)

Also called Korean Angelica, Giant Purple Angelica, Korean Masterwort (Angelica gigas).

More about korean angelica

About Korean Angelica

Angelica gigas · also called Korean Angelica, Giant Purple Angelica · flowering

Korean Angelica is a dramatic biennial or short-lived perennial prized for its deep burgundy-purple umbel flowers and bold, architectural foliage. It thrives in moist, humus-rich soil with partial shade and cool conditions. Plants self-seed freely, making them naturalise well in woodland gardens and damp borders.

Plant type: flowering

Watch for — Aphid infestations on stems: Dense colonies of aphids often target the hollow flower stems and leaf axils. Knock off with a strong water jet or apply insecticidal soap. Encourage predatory insects such as ladybirds and lacewings.

The reasons korean angelica isn't blooming

Almost every non-blooming korean angelica 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 korean angelica 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 korean angelica to flower

Maximise sun. Give korean angelica 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 korean angelica and get the feeding right with the korean angelica 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

Korean Angelica 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 korean angelica care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Korean Angelica blooming — frequently asked questions

Why won't my korean angelica flower?

Korean Angelica 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 korean angelica bloom?

Give korean angelica 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 korean angelica normally bloom?