Why is my rose not flowering?

Working through light, feeding, pruning, suckers and rose replant disease to find why a rose produces growth and no blooms.

Difficulty: beginner
Time: 25 min
Read: 3 min

Short answer

Check for suckers first — vigorous growth from below the graft with different leaves flowers poorly or not at all and takes over the plant. After that, the usual causes are too much shade, too much nitrogen, or pruning at the wrong time.

Roses are among the most demanding garden plants for light and food, and they are one of the few where the rootstock can quietly replace the variety you bought without anyone noticing for a couple of years.

Step by step

Look for suckers below the graft union.The graft is the knobbly swelling at the base. Growth coming from below it, often with seven leaflets rather than five and a different leaf colour, is rootstock. It flowers poorly and outgrows the variety.
Remove suckers by tearing, not cutting.Trace the sucker back to where it joins the root, and pull it away sharply. Cutting leaves dormant buds that produce several suckers in its place.
Assess the light.Most roses need at least six hours of direct sun. A rose that flowered well and gradually stopped is often being shaded by something that has grown up around it.
Check what is being fed nearby.A rose in or beside a fed lawn gets nitrogen, which produces leaf and shoot growth at the expense of flower. Rose feeds are potash-rich for exactly this reason.
Feed correctly.A proprietary rose feed or sulphate of potash in early spring, and again after the first flush for repeat-flowering varieties. Mulch with compost after feeding.
Check the pruning.Repeat-flowering roses are pruned hard in late winter. Once-flowering ramblers flower on last year's wood and are pruned after flowering — cut them in winter and you remove the flowers.
Deadhead repeat-flowering varieties.Cutting spent blooms back to an outward-facing five-leaflet leaf triggers the next flush. Left to set hips, the plant stops.
Water deeply in dry spells.Roses are deep-rooted and need a proper soak rather than a sprinkle. Drought in June reduces the later flushes considerably.
Consider rose replant disease.A new rose planted where a rose grew before often sulks and never establishes. Replace the soil in the planting hole with soil from elsewhere in the garden, or plant somewhere new.
Check for pests and disease weakening the plant.Heavy blackspot defoliation, or aphids on every shoot tip, reduce flowering substantially. A plant with no leaves in July has nothing to flower with.

Tips

Seven leaflets and a different leaf colour usually means a rootstock sucker.
Tear suckers off, do not cut them — cutting multiplies them.
A rose in a fed lawn is being given nitrogen whether you intended it or not.

Common mistakes

Cutting suckers off at ground level — It leaves the base of the sucker with dormant buds, and three come back where one was. They have to be traced to the root and torn away.
Pruning a rambling rose in winter — Ramblers flower on wood made the previous year. Winter pruning removes the entire display. They are pruned straight after flowering.

If it doesn't work

Vigorous thorny growth with different leaves

Cause: Rootstock suckers — Fix: Trace to the root and tear away. Repeat as they appear.

Plenty of leaf, no buds

Cause: Excess nitrogen or insufficient light — Fix: Switch to a potash-rich rose feed and assess whether the plant is being shaded.

One flush then nothing

Cause: Not deadheaded, or a once-flowering variety — Fix: Deadhead to an outward-facing five-leaflet leaf, and feed after the first flush.

New rose never established

Cause: Rose replant disease — Fix: Lift it, replace the planting hole soil with soil from elsewhere, and replant with mycorrhizal fungi.

Questions people ask

What is a rose sucker and how do I tell?

Growth from the rootstock below the graft union. It is usually more vigorous, often thornier, frequently has seven leaflets instead of five, and is a different shade of green.

Why did my rose flower well and then stop?

Usually increasing shade from something growing nearby, or nitrogen from a lawn feed. Both develop gradually, which is why the decline is gradual too.

Can I plant a new rose where an old one was?

Not without changing the soil. Rose replant disease stunts new roses in old rose soil. Dig out a generous hole and replace the soil with some from elsewhere in the garden.