Why are my plants flowering at the wrong time of year?
The five reasons plants flower out of season — mild weather, stress, pruning at the wrong moment, a second flush and simple normality — and which of them are worth doing anything about.
- Difficulty
- beginner
- Time
- 10 min
- Read
- 4 min
Short answer
Most out-of-season flowering is either normal for that plant, or a response to weather that has confused its dormancy, or a stress response — and none of the three needs action. The two worth investigating are flowering triggered by pruning at the wrong time, which you can avoid repeating, and a plant that flowers repeatedly out of season and never properly in it, which is usually a light or feeding problem.
A rose in December or a shrub flowering in autumn generates a lot of concern and almost never needs any. Plants judge the season by temperature and day length, and both of those can send mixed signals — but the plant is usually reading the situation correctly and doing something reasonable about it.
Step by step
- Establish whether it is normal for that plant.A surprising number of garden plants flower in autumn or winter as a matter of course, and many roses and repeat-flowering perennials will carry on well past when people expect. Check the plant before assuming anything is wrong.
- Consider the weather in the preceding months.A cool wet summer followed by a warm autumn is the classic trigger for out-of-season flowering, because the plant experienced something resembling a winter and then a spring.
- Look for signs of stress.Heavy unseasonal flowering alongside poor growth, small leaves, early leaf drop or dieback is a plant in trouble. Check for drought, waterlogging, root damage, a pot-bound root system or damage at the base of the stem.
- Think about what you pruned and when.Pruning stimulates growth, and growth late in the season can carry flowers into autumn. More importantly, pruning at the wrong moment removes the wood that would have flowered in the proper season.
- Decide whether anything is actually lost.For most out-of-season flowering, the answer is a small part of next season's display and nothing else. That is not worth intervening over.
- Act only on the stress case and the pruning case.Relieve stress where you find it, and correct your pruning timing for next year. Everything else on this list is the plant behaving reasonably.
Tips
- Deadheading is a deliberate way of causing out-of-season flowering, and it works because setting seed is what tells a plant it has finished.
- Bulb foliage emerging early is very rarely a problem. It is the flower buds that are vulnerable, and only to a hard frost at exactly the wrong moment.
- A fruit tree flowering in autumn loses that portion of next year's blossom. On a heavily-cropping tree that is negligible; on a young or single-branch tree it is worth noting but still not worth acting on.
- Plants moved or repotted often flower unseasonally the following year while they re-establish. It settles down.
- Mild winters bring blossom forward into the frost window, which is a much bigger practical issue than out-of-season flowering itself.
If it doesn't work
A spring-flowering shrub produces a few flowers in a mild autumn
Cause: A warm autumn following a cool or stressed summer can partially break dormancy on buds that were formed for spring — Fix: Nothing. It costs the plant a small fraction of next spring's display and it will flower more or less normally. Do not prune in response.
Bulbs emerging early in a mild winter
Cause: Bulbs respond to soil temperature, and a mild winter starts them moving sooner — Fix: Leave them. Foliage is tough and takes frost without lasting harm. If flower buds are showing and a hard frost is forecast, a covering of fleece or a mulch of leaves over them is a reasonable precaution.
A plant flowers unusually heavily and early, then looks poor
Cause: Stress flowering — a plant under real pressure from drought, root damage, waterlogging or being pot-bound puts its resources into reproducing — Fix: Find and relieve the stress rather than admiring the flowers. Check the roots, the water and the drainage. This is the one pattern that is genuinely a warning.
A second, smaller flush of flowers after the main one
Cause: Normal repeat flowering, or a response to deadheading, or a mild autumn extending the season — Fix: Nothing — enjoy it. Deadheading is often the direct cause, since removing spent flowers stops the plant setting seed and it flowers again instead.
A shrub flowers sparsely at the wrong time every year and never properly in its season
Cause: Usually pruning at the wrong moment — cutting off the wood that carries next season's flower buds — or too little light, or too much nitrogen — Fix: Establish whether the shrub flowers on old wood or new, and prune accordingly and at the right time. If pruning is not the cause, look at light levels and stop feeding with a high-nitrogen fertiliser.
Questions people ask
Should I remove out-of-season flowers?
Generally no. The energy has already gone into producing them. The exception is a young or newly planted specimen you want to put its resources into establishing, where removing flowers is a reasonable choice.
Will it flower normally next year?
Almost always yes, minus whatever proportion of buds it used early. A plant flowering out of season because of stress will only return to normal once the stress is relieved.
Is this a sign of climate change?
Milder autumns and winters do make out-of-season flowering more common, and the trend is real. In an individual garden in an individual year it is far more likely to be that plant, that weather and that pruning.