Getting it to bloom

Why won't my Thyme-leaved Sandwort bloom? (and how to make it flower)

Also called Thyme-leaved Sandwort, Thymeleaf Sandwort (Arenaria serpyllifolia).

More about thyme-leaved sandwort

About Thyme-leaved Sandwort

Arenaria serpyllifolia · also called Thyme-leaved Sandwort, Thymeleaf Sandwort · flowering

Arenaria serpyllifolia is a delicate annual or biennial in the family Caryophyllaceae, native to dry, disturbed, and open habitats across Europe, Asia, and North Africa, and widely naturalised in North America. It produces tiny five-petalled white flowers from May to October on slender, much-branched stems clothed in small, ovate leaves that superficially resemble those of thyme. The most important care fact is excellent drainage: it thrives in gritty, infertile soils and is intolerant of waterlogged conditions. No toxicity to pets has been established for this species.

Plant type: flowering

The reasons thyme-leaved sandwort isn't blooming

Almost every non-blooming thyme-leaved sandwort 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 thyme-leaved sandwort 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 thyme-leaved sandwort to flower

Maximise sun. Give thyme-leaved sandwort 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 thyme-leaved sandwort and get the feeding right with the thyme-leaved sandwort 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

Thyme-leaved Sandwort 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 thyme-leaved sandwort care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Thyme-leaved Sandwort blooming — frequently asked questions

Why won't my thyme-leaved sandwort flower?

Thyme-leaved Sandwort 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 thyme-leaved sandwort bloom?

Give thyme-leaved sandwort 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 thyme-leaved sandwort normally bloom?