Getting it to bloom

Why won't my Night-scented stock bloom? (and how to make it flower)

Also called Night-scented stock, Evening stock, Perfume plant, Gilly flower (Matthiola longipetala).

More about night-scented stock

About Night-scented stock

Matthiola longipetala · also called Night-scented stock, Evening stock · flowering

Night-scented stock is a fast-growing hardy annual whose small, purple or pale lilac flowers appear modest by day — petals fold inward in sunlight — but open wide at dusk, releasing an extraordinarily powerful, sweet fragrance. Sow directly into beds in full sun, water sparingly, and expect flowers within 6–8 weeks from seed.

Plant type: flowering

Watch for — Poor or no fragrance: Flowers only release full fragrance from early evening onward — this is normal behaviour. If fragrance is weak, ensure plants receive sufficient sun and are not overcrowded. Heat above 25°C (77°F) can shorten flower life and reduce scent intensity.

The reasons night-scented stock isn't blooming

Almost every non-blooming night-scented stock 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 night-scented stock 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 night-scented stock to flower

Maximise sun. Give night-scented stock 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 night-scented stock and get the feeding right with the night-scented stock 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

Night-scented stock 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 night-scented stock care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Night-scented stock blooming — frequently asked questions

Why won't my night-scented stock flower?

Night-scented stock 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 night-scented stock bloom?

Give night-scented stock 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 night-scented stock normally bloom?