Damage rating


Type of disorder

Premature production of flowers and seed.


How to recognise it

Vegetables will flower and go to seed before being ready to harvest.

What causes it

Often it is caused by sowing or planting too early in the season, as plants require a period of cold at a certain point in their growth cycle. Once they have received that period of cold they will be triggered to flower and seed at a specific point (although this is also influenced by day length).

A shortage of water can also cause bolting as it puts the plant under stress and induces flower formation.

Why it’s a problem

It can cause the loss of crops if they bolt before maturity (ie before they are ready to harvest).

Where you are likely to find it

Commonly occurs with vegetables such as onions, beetroot, celery, lettuce and spinach, particularly on vegetables planted in colder weather for earlier cropping.

How to prevent it

Bolt-resistant varieties are available for most vegetables. It is more prevalent on earlier varieties, so selecting later crops will help reduce the risk.

Ensure that plants are well watered in drought conditions.

How to get rid of it

There is nothing you can do to prevent bolting once the environmental conditions have triggered it.

Is it good for anything?!

Not really, but it’s interesting to note that ornamental plants which are a little too well looked after can fail to flower because, conversely to bolting, they have not been put under enough stress to flower.