Getting it to bloom

Why won't my Annual Phlox 'Sugar Stars' bloom? (and how to make it flower)

Also called Annual phlox, Drummond phlox (Phlox drummondii 'Sugar Stars').

More about annual phlox 'sugar stars'

About Annual Phlox 'Sugar Stars'

Phlox drummondii 'Sugar Stars' · also called Annual phlox, Drummond phlox · flowering

'Sugar Stars' is an annual phlox with distinctive star-shaped, lavender-blue petals edged and centred in white. A bushy, free-flowering Texas native annual, it blooms from late spring through summer in dense fragrant clusters, excellent for borders, containers and cutting. It performs best in cool to mild conditions and loves full sun.

Plant type: flowering

Watch for — Leggy growth: Stretches and flowers poorly in too little light; pinch young plants and grow in full sun to keep them bushy.

The reasons annual phlox 'sugar stars' isn't blooming

Almost every non-blooming annual phlox 'sugar stars' 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 annual phlox 'sugar stars' 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 annual phlox 'sugar stars' to flower

Maximise sun. Give annual phlox 'sugar stars' 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 annual phlox 'sugar stars' and get the feeding right with the annual phlox 'sugar stars' 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

Annual Phlox 'Sugar Stars' 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 annual phlox 'sugar stars' care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Annual Phlox 'Sugar Stars' blooming — frequently asked questions

Why won't my annual phlox 'sugar stars' flower?

Annual Phlox 'Sugar Stars' 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 annual phlox 'sugar stars' bloom?

Give annual phlox 'sugar stars' 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 annual phlox 'sugar stars' normally bloom?