Getting it to bloom

Why won't my Thalictrum delavayi 'Hewitt's Double' bloom? (and how to make it flower)

Also called Hewitt's Double meadow rue (Thalictrum delavayi 'Hewitt's Double').

More about thalictrum delavayi 'hewitt's double'

About Thalictrum delavayi 'Hewitt's Double'

Thalictrum delavayi 'Hewitt's Double' · also called Hewitt's Double meadow rue · flowering

'Hewitt's Double' is a tall, airy meadow rue prized for clouds of tiny, fully double lilac-mauve pompon flowers held on wiry stems above delicate, fern-like blue-green foliage in mid to late summer. A graceful herbaceous perennial reaching 1.2-1.8 m, it brings see-through height to the middle or back of a moist, partly shaded border.

Plant type: flowering

Watch for — Slow to establish: It can sulk and flower sparsely in its first year or two; give it time, cool moist soil, and avoid disturbing the roots once settled.

The reasons thalictrum delavayi 'hewitt's double' isn't blooming

Almost every non-blooming thalictrum delavayi 'hewitt's double' 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 thalictrum delavayi 'hewitt's double' 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 thalictrum delavayi 'hewitt's double' to flower

Maximise sun. Give thalictrum delavayi 'hewitt's double' 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 thalictrum delavayi 'hewitt's double' and get the feeding right with the thalictrum delavayi 'hewitt's double' 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

Thalictrum delavayi 'Hewitt's Double' 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 thalictrum delavayi 'hewitt's double' care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Thalictrum delavayi 'Hewitt's Double' blooming — frequently asked questions

Why won't my thalictrum delavayi 'hewitt's double' flower?

Thalictrum delavayi 'Hewitt's Double' 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 thalictrum delavayi 'hewitt's double' bloom?

Give thalictrum delavayi 'hewitt's double' 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 thalictrum delavayi 'hewitt's double' normally bloom?