Getting it to bloom

Why won't my Crystal Palace lobelia bloom? (and how to make it flower)

Also called Crystal Palace lobelia, edging lobelia, trailing lobelia, annual lobelia (Lobelia erinus 'Crystal Palace').

More about crystal palace lobelia

About Crystal Palace lobelia

Lobelia erinus 'Crystal Palace' · also called Crystal Palace lobelia, edging lobelia · flowering

Crystal Palace lobelia is a compact, mounding cultivar of Lobelia erinus bearing a dense carpet of deep navy-blue flowers with a white eye above dark bronze-green foliage. A cool-season annual, it thrives in bright conditions with consistent moisture and is ideal for edging, containers and hanging baskets. Contains lobeline alkaloids — treat as toxic to pets.

Plant type: flowering

Watch for — Grey mould (Botrytis cinerea): Dense flower heads and moist, still conditions encourage Botrytis — improve airflow, avoid overhead watering and remove spent blooms promptly.

The reasons crystal palace lobelia isn't blooming

Almost every non-blooming crystal palace lobelia 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 crystal palace lobelia 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 crystal palace lobelia to flower

Maximise sun. Give crystal palace lobelia 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 crystal palace lobelia and get the feeding right with the crystal palace lobelia 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

Crystal Palace lobelia 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 crystal palace lobelia care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Crystal Palace lobelia blooming — frequently asked questions

Why won't my crystal palace lobelia flower?

Crystal Palace lobelia 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 crystal palace lobelia bloom?

Give crystal palace lobelia 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 crystal palace lobelia normally bloom?