Getting it to bloom

Why won't my Oriental Bittersweet bloom? (and how to make it flower)

Also called Asian Bittersweet, Round-leaved Bittersweet, Chinese Bittersweet (Celastrus orbiculatus).

More about oriental bittersweet

About Oriental Bittersweet

Celastrus orbiculatus · also called Asian Bittersweet, Round-leaved Bittersweet · flowering

Oriental Bittersweet is a vigorous deciduous woody vine originally from eastern Asia, widely considered an invasive species in North America. It produces attractive orange-and-red berries along the full length of its stems. All parts are toxic to pets; cultivation is discouraged or illegal in many US states.

Plant type: flowering

The reasons oriental bittersweet isn't blooming

Almost every non-blooming oriental bittersweet 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 oriental bittersweet 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 oriental bittersweet to flower

Maximise sun. Give oriental bittersweet 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 oriental bittersweet and get the feeding right with the oriental bittersweet 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

Oriental Bittersweet 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 oriental bittersweet care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Oriental Bittersweet blooming — frequently asked questions

Why won't my oriental bittersweet flower?

Oriental Bittersweet 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 oriental bittersweet bloom?

Give oriental bittersweet 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 oriental bittersweet normally bloom?