Why Have My Carrots Bolted (and can I still eat them)?

Carrots are one of the most popular vegetables for the homesteader to grow. They are tasty, easy to store and they can be grown in a relatively small area.

Carrots are biennial, meaning they produce their roots in the first year, then send up a flowerhead that produces seeds in their second year.

Sometimes however things go wrong and the carrots flower in year one. In this article, I look at the reasons why carrots sometimes run to seed early, which is often referred to as ‘bolting’, and how we can prevent it from happening.

There can be a number of reasons your carrots have bolted, but a sudden cold spell, a lack of water, or stress caused by the carrots being attacked by a pest such as a carrot root fly are the most likely causes. Carrots that have bolted are generally too fibrous and ‘woody’ to eat.

Why Have My Carrots Bolted?

It can be incredibly frustrating when you look down the row of fluffy green carrot tops protruding from the ground, only to find signs the carrots are sending flower spikes up.

Carrots are biennial, which means they grow over a two-year period. In the first year they grow the bright orange roots they are so famed for, and then in the second year, they send up a surprisingly attractive flower spike which will eventually turn into thousands of paper-thin seeds.

There can be a number of different reasons that carrots bolt. Some of them are preventable, whereas others are just out of your control.

The most likely reasons carrots bolt are

  • A sudden cold spell of weather
  • Very warm weather
  • Lack of water
  • Pests such as Carrot Root Fly

A sudden cold spell of weather

The weather is clearly something that is out of our control, and it can be both our best friend and our worst enemy.

As mentioned above, carrots are biennial. They sit in the soil for two years before completing their life cycle.

The only way a carrot knows what season it is growing in is by temperature. A period of cold weather tells the carrot winter has arrived, and when it warms up again, it is time to throw a seed head up.

The problem is, if we experience a cold snap in the first few months of a carrot’s life, the plants may believe winter has arrived. They will promptly stop growing and wait for the next spell of warm weather.

Once the cold snap passes, the carrots believe they are in year two and they will start to flower.

In my experience, the best way to prevent your carrots from running to seed thanks to a cold spell, is to cover them lightly with some horticultural fleece (such as this one I recently purchased from Amazon.com).

The horticultural fleece will keep the carrots a degree or two warmer than the surrounding area, hopefully preventing the carrots from thinking winter has arrived.

Very warm weather

Warm weather can also cause carrots to run to seed early. The carrots can become stressed due to the additional heat, and when carrots are stressed they go into survival mode.

A carrot’s sole aim in life is to produce the next generation via seeds. If the stress caused by the extra warm weather makes the carrots believe they are going to perish, they will likely send up a seed head in an attempt to ensure the next generation survives.

Ironically, as with cold weather, throwing some horticultural fleece over the growing carrots can keep the worst of the sun off of them, helping prevent them from becoming stressed thanks to the strong sun and high heat.

Lack of water

A lack of water can send the carrots into exactly the same survival mode as when the temperatures are too high.

A carrot root has only two jobs to do. one, store energy (which is the bit we eat), and two, grow deep down into the soil in search of moisture.

In most years the subsoil has more than enough water to match the carrot’s needs, but in very dry years, or if the carrots are being grown in containers, there may not be sufficient water.

To prevent a carrot from running to seed thanks to lack of water, we will need to supply the plants with additional water. However, it does the carrots little good if we just wet the surface every day.

Most of us want long, thick carrots, and to create those long roots, we need the carrots to continue to grow down in search of moisture.

If we just sprinkle the surface with water, the roots will stop growing down and instead head for the surface, creating short, twisted carrots which are often of little use to us.

Instead, you are better to water the carrots A LOT, once a week. By adding a lot of water, that water will end up penetrating deep into the soil right where the carrots need it.

When I water my own carrots, I will often give them 5 gallons (19 liters) of water or more per 6′ (1.83m) row.

By pouring on so much water, you give your carrots a much better chance of continuing to grow down deep into the subsoil.

Pests such as Carrot Root Fly

There are a number of pests that will attack carrots, but the humble Carrot Root Fly is probably the most well-known.

By this point in the article, you are probably familiar with what happens when carrots become stressed, and a large infestation of pests can also cause the carrots stress and trigger their survival mode.

Once again, covering the entire crop of carrots in horticultural fleece is probably your best defense against almost all pests.

Can You Eat Carrots That Have Bolted?

Whilst carrots that have bolted would not do you any harm, they are essentially edible, the flowering process causes the center (and in fact the majority of the carrot) to become hard and fibrous.

Carrots that have bolted are often described as being ‘woody’.

Bolted carrots can also lose a lot of the sweetness carrots are famed for and may even become very bitter. In my opinion, bitter carrots are pretty much inedible.


Unfortunately, bolting is a natural process that can sometimes catch us off guard. Most years carrots won’t bolt.

By keeping an eye on our carrots, and the weather, the chances are we can prevent our carrots from bolting.

Keeping a roll of horticultural fleece on hand, just in case, is a great way to prevent your carrots from bolting should nature conspire against you.

If you found this article helpful, why not check out another one I wrote recently titled Why Does My Celeriac Bolt?

Arya Patel

Arya Patel is HomesteadSavvy.com’s fruit and vegetable editor. Arya has been homesteading for well over a decade and over that time she has grown countless varieties of fruits and vegetables. She aims to become completely self-sufficient over the next 5 years.
Fruit & Vegetable Editor

Article Sources:

  1. Carrots Wikipedia