Getting it to bloom

Why won't my Common Broom bloom? (and how to make it flower)

Also called Common broom, Scotch broom, Broom (Cytisus scoparius).

More about common broom

About Common Broom

Cytisus scoparius · also called Common broom, Scotch broom · flowering

Cytisus scoparius is a deciduous to semi-evergreen shrub native to western and central Europe, common on heathlands, dry banks, and road verges across the British Isles. It produces masses of bright yellow pea-flowers on arching green stems in late spring and early summer and is adapted to dry, infertile, acidic soils in full sun. The key care rule is to never cut into old wood — pruning must always leave green stems — as the plant does not regenerate from bare wood and old untended plants quickly become untidy and collapse. Common broom is toxic to dogs and cats due to quinolizidine alkaloids.

Plant type: flowering

Watch for — Broom gall mite (Aceria genistae): Causes tight, cauliflower-like galls at stem tips; prune out affected growth in winter. The mite is species-specific and does not spread to other garden plants.

The reasons common broom isn't blooming

Almost every non-blooming common broom 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 common broom 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 common broom to flower

Maximise sun. Give common broom 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 common broom and get the feeding right with the common broom 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

Common Broom 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 common broom care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Common Broom blooming — frequently asked questions

Why won't my common broom flower?

Common Broom 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 common broom bloom?

Give common broom 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 common broom normally bloom?