Getting it to bloom

Why won't my Summer Skies delphinium bloom? (and how to make it flower)

Also called Summer Skies delphinium, Summer Skies larkspur (Delphinium elatum 'Summer Skies').

More about summer skies delphinium

About Summer Skies delphinium

Delphinium elatum 'Summer Skies' · also called Summer Skies delphinium, Summer Skies larkspur · flowering

A classic Pacific Giant hybrid of Delphinium elatum bearing enormous, densely packed flower spikes of pale sky-blue with a white or light bee (central floret). Growing to around 180–210 cm, it is one of the tallest garden delphiniums. Like all delphiniums, it is highly toxic to pets. Demands rich, well-drained soil in full sun and mandatory staking against wind damage.

Plant type: flowering

Watch for — Powdery mildew: Dense flower spikes trap humid air and promote mildew after bloom. Space plants well, water at the base, remove spent spikes promptly, and spray with potassium bicarbonate at the first signs.

The reasons summer skies delphinium isn't blooming

Almost every non-blooming summer skies delphinium 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 summer skies delphinium 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 summer skies delphinium to flower

Maximise sun. Give summer skies delphinium 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 summer skies delphinium and get the feeding right with the summer skies delphinium 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

Summer Skies delphinium 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 summer skies delphinium care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Summer Skies delphinium blooming — frequently asked questions

Why won't my summer skies delphinium flower?

Summer Skies delphinium 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 summer skies delphinium bloom?

Give summer skies delphinium 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 summer skies delphinium normally bloom?