Getting it to bloom

Why won't my Tall Goldenrod bloom? (and how to make it flower)

Also called tall goldenrod, late goldenrod, Canada goldenrod (Solidago altissima).

More about tall goldenrod

About Tall Goldenrod

Solidago altissima · also called tall goldenrod, late goldenrod · flowering

Tall goldenrod is a vigorous native prairie perennial that lights up late summer and autumn with arching plumes of tiny golden flowers, feeding migrating monarchs and countless pollinators. It spreads by rhizomes into bold colonies, thriving in sun and tolerating poor, dry soil. Best in meadows and naturalistic plantings where its spread is welcome.

Plant type: flowering

Watch for — Hay-fever misblame: Often wrongly accused of causing allergies; its pollen is insect-borne and heavy. The real culprit is ragweed, which blooms at the same time.

The reasons tall goldenrod isn't blooming

Almost every non-blooming tall goldenrod 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 tall goldenrod 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 tall goldenrod to flower

Maximise sun. Give tall goldenrod 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 tall goldenrod and get the feeding right with the tall goldenrod 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

Tall Goldenrod 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 tall goldenrod care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Tall Goldenrod blooming — frequently asked questions

Why won't my tall goldenrod flower?

Tall Goldenrod 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 tall goldenrod bloom?

Give tall goldenrod 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 tall goldenrod normally bloom?