Getting it to bloom

Why won't my Toothed Nemesia bloom? (and how to make it flower)

Also called Toothed Nemesia, Nemesia (Nemesia denticulata).

More about toothed nemesia

About Toothed Nemesia

Nemesia denticulata · also called Toothed Nemesia, Nemesia · flowering

Nemesia denticulata is a mat-forming perennial native to South Africa, distinguished by its slightly toothed and wavy-edged petals that appear in shades of light purple to pale lilac through summer and early autumn. It thrives in cool conditions with fertile, moist but well-drained soil in full sun, and will pause flowering during very hot dry spells before resuming when temperatures drop. Pinch out growing tips when young to encourage a bushy habit, and trim back after the first flush to promote a second wave of bloom. It is not listed in the ASPCA database, and no toxic principles are documented for the genus.

Plant type: flowering

Watch for — Heat-induced flowering pause: Plants often stop blooming in midsummer heat above 25°C; trim back spent stems and ensure adequate watering and the plant will reflower as temperatures cool.

The reasons toothed nemesia isn't blooming

Almost every non-blooming toothed nemesia 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 toothed nemesia 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 toothed nemesia to flower

Maximise sun. Give toothed nemesia 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 toothed nemesia and get the feeding right with the toothed nemesia 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

Toothed Nemesia 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 toothed nemesia care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Toothed Nemesia blooming — frequently asked questions

Why won't my toothed nemesia flower?

Toothed Nemesia 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 toothed nemesia bloom?

Give toothed nemesia 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 toothed nemesia normally bloom?