Getting it to bloom

Why won't my Shrubby St John's Wort bloom? (and how to make it flower)

Also called Rose of Sharon, Aaron's beard, creeping St John's wort (Hypericum calycinum).

More about shrubby st john's wort

About Shrubby St John's Wort

Hypericum calycinum · also called Rose of Sharon, Aaron's beard · flowering

Hypericum calycinum is a low, spreading evergreen-to-semi-evergreen subshrub grown as tough groundcover. It bears large golden-yellow flowers with prominent boss-like stamens through summer and roots from spreading stolons to knit dense, weed-smothering cover. Adaptable to sun or shade and poor, dry soil, it is vigorous to the point of becoming invasive.

Plant type: flowering

Watch for — Poor flowering in deep shade: Tolerates shade but blooms sparsely there; move to brighter positions for maximum flower.

The reasons shrubby st john's wort isn't blooming

Almost every non-blooming shrubby st john's wort 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 shrubby st john's wort 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 shrubby st john's wort to flower

Maximise sun. Give shrubby st john's wort 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 shrubby st john's wort and get the feeding right with the shrubby st john's wort 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

Shrubby St John's Wort 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 shrubby st john's wort care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Shrubby St John's Wort blooming — frequently asked questions

Why won't my shrubby st john's wort flower?

Shrubby St John's Wort 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 shrubby st john's wort bloom?

Give shrubby st john's wort 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 shrubby st john's wort normally bloom?