Getting it to bloom

Why won't my Montgomery Astilbe bloom? (and how to make it flower)

Also called Montgomery astilbe, red Japanese astilbe (Astilbe japonica 'Montgomery').

More about montgomery astilbe

About Montgomery Astilbe

Astilbe japonica 'Montgomery' · also called Montgomery astilbe, red Japanese astilbe · flowering

Montgomery is a Japanese astilbe grown for dense, upright plumes of deep crimson-red flowers in early to midsummer above glossy, bronze-tinged ferny foliage. A clump-forming shade perennial, it thrives in consistently moist, humus-rich soil and is ideal for damp borders, pond margins, and woodland edges where many other flowering plants struggle.

Plant type: flowering

Watch for — Poor flowering: Too much shade or insufficient moisture reduces plume production; give part shade and reliably wet, fertile soil.

The reasons montgomery astilbe isn't blooming

Almost every non-blooming montgomery astilbe 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 montgomery astilbe 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 montgomery astilbe to flower

Maximise sun. Give montgomery astilbe 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 montgomery astilbe and get the feeding right with the montgomery astilbe 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

Montgomery Astilbe 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 montgomery astilbe care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Montgomery Astilbe blooming — frequently asked questions

Why won't my montgomery astilbe flower?

Montgomery Astilbe 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 montgomery astilbe bloom?

Give montgomery astilbe 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 montgomery astilbe normally bloom?