Getting it to bloom

Why won't my Black Prince snapdragon bloom? (and how to make it flower)

Also called Black Prince snapdragon, Dark snapdragon, Crimson snapdragon (Antirrhinum majus 'Black Prince').

More about black prince snapdragon

About Black Prince snapdragon

Antirrhinum majus 'Black Prince' · also called Black Prince snapdragon, Dark snapdragon · flowering

Black Prince is a striking heirloom snapdragon with deep velvety crimson-red flowers contrasting against bronze-green, dark-flushed foliage. Growing 45–60 cm tall, it is a stand-out plant for gothic, monochrome, or jewel-toned borders and an excellent cut flower. It blooms in cool weather, performing best in spring and autumn in most climates.

Plant type: flowering

Watch for — Aphids: Colonies form on new growth and buds, especially in spring. The dark foliage makes early infestations easy to overlook. Inspect regularly and treat with insecticidal soap or a strong water jet.

The reasons black prince snapdragon isn't blooming

Almost every non-blooming black prince snapdragon 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 black prince snapdragon 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 black prince snapdragon to flower

Maximise sun. Give black prince snapdragon 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 black prince snapdragon and get the feeding right with the black prince snapdragon 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

Black Prince snapdragon 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 black prince snapdragon care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Black Prince snapdragon blooming — frequently asked questions

Why won't my black prince snapdragon flower?

Black Prince snapdragon 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 black prince snapdragon bloom?

Give black prince snapdragon 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 black prince snapdragon normally bloom?