Getting it to bloom

Why won't my Sweet Box bloom? (and how to make it flower)

Also called Sweet Box, Slender Sweet Box (Sarcococca hookeriana var. digyna).

More about sweet box

About Sweet Box

Sarcococca hookeriana var. digyna · also called Sweet Box, Slender Sweet Box · flowering

Sarcococca hookeriana var. digyna is a shade-loving evergreen shrub grown for intensely fragrant tiny white winter flowers and glossy dark leaves on slender, suckering stems. The vanilla-scented blooms perfume cold gardens before berries form. Tolerant of deep, dry shade once established, it is an invaluable structural plant for shaded borders, hedging, and pots near paths and doorways.

Plant type: flowering

Watch for — Sparse flowering: Too much sun and dryness reduce the fragrant winter bloom; site in cooler shade with consistent moisture.

The reasons sweet box isn't blooming

Almost every non-blooming sweet box 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 sweet box 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 sweet box to flower

Maximise sun. Give sweet box 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 sweet box and get the feeding right with the sweet box 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

Sweet Box 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 sweet box care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Sweet Box blooming — frequently asked questions

Why won't my sweet box flower?

Sweet Box 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 sweet box bloom?

Give sweet box 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 sweet box normally bloom?