Carrots are one of the best crops for home gardeners to grow, the difference in taste between carrots bought in the supermarket and those freshly picked from the garden is astounding. Home grown carrots are incredibly sweet, crunchy and delicious.
In this article I will teach you step by step how to grow and plant your own carrots from seed. In as little as 12 weeks you can be picking fresh carrots from your own garden.
There are a few important things you must first consider before we can begin planting carrot seeds. First of all it’s very important to know that carrots should never be sown in the same place for two consecutive years, this will lead to a build up of pests and a 3 year crop rotation is essential for carrots.
Carrots like to be grown in a light fine soil that hasn’t had manure added in the last 12 months. The plants are not hungry feeders but if your soil is very poor then adding a blood fish and bone fertiliser will help with growth.
When To Plant Your Carrot Seeds
Most carrots are sown from the second week in April until the second week of May in the UK.
Sowings can be made far earlier in the season either using cloches or growing in containers in a greenhouse. Weather permitting you can begin sowing early varieties as soon as the first week of March if you are able to provide some protection. The weather early in the season can be unpredictable so if a heavy snow or frost is forecasted, hold off sowing until the worst of the weather has passed.
Cloches in particular can really give you an early crop. Place the cloche on the soil where you are going to be sowing your carrot seeds for at least a week before you begin sowing to give it time to warm the temperature of the soil. It is said that a cloche can increase the soil temperature by up to 10 degrees which will significantly increase germination rates of early sown seeds.
Carrots need a soil temperature of between 7°C and 29°C, but 10°C is ideal. If you are not sure what temperature your soil is, you can use a soil thermometer.
My Recommended Soil Thermometer:
- ESSENTIAL SOIL THERMOMETER - A popular soil temperature probe thermometer which can be used in the garden or greenhouse prior to sowing and planting
- STYLISH HANDY DESIGN! - This soil thermometer has a green plastic top to easily hold and insert into soil and compost. The temperature scale is also very clear to read.
- FANTASTIC VALUE - When it comes to soil thermometers, we only offer the best quality and accuracy and this item is just that!
Maincrop carrots are better planted a little later in the season, the last week in April being the ideal time. Maincrop varieties are intended to be grown until they are quite large and are ideal for harvesting in late summer and storing for later use
How To Sow Carrots
Make a seed drill about 2cm (about 3⁄4 of an inch) deep and space the rows 15cm (6 inches) apart. Seeds should be sown 1cm (1⁄2 inch) apart.
Carrot seeds are tiny and very difficult to sow evenly. There is a trick to sowing carrot seeds done by a lot of the experts which results in far more even distribution.
This is done by mixing the tiny carrot seeds with some dry sand, by doing so you make the seed far easier to spread in the drills as well as being able to see exactly where you have sown.
Carrot seeds are relatively inexpensive and the packets are generous so sowing a little thicker than you need isn’t the end of the world, you will just need to spend a little more time thinning the plants out when they germinate.
Using “seed tapes” is also an option but they are significantly more expensive than simply buying seeds.
Once sown cover with a very light layer of soil. Carrot germination can be slow but in good conditions you should begin to see the plants coming up after 14 days.
Growing Your Carrots On
Once planted carrots do not need a whole lot of looking after. After germination thinning the plants to a spacing of 2.5cm (1 inch) will give the strongest possible plants. Weeding in the first few months is important.
By planting your rows at a 15cm (6 inch) spacing once the plants begin to grow they will shade the soil and stop most weeds being able to grow, this reduces the amount of work you should need to do.
Carrots do not need any liquid feeds in the growing season, high nitrogen feeds will actually lead to the growth of a lot of lush green leaves but really doesn’t help the roots growing at all.
Watering in dry weather will give your carrots an advantage but they will survive fairly dry conditions.
Harvesting Your Carrots
Carrots taste the best when they are still small and tender, this will usually be about 12 weeks after sowing. Main crop carrots are usually left to become larger and can be stored over the winter months. The top of the carrot is usually showing above the soil – or you can slightly uncover the carrot – and that will give you a really good idea of size.
Top tip: For best taste, pick as soon as the carrots are big enough. The bigger they grow the less tasty they are.
You can carefully pull them out holding them at the top of the root or you can use a fork to lift them out. This might be needed if the soil is heavy.
Carrot Pest & Diseases
Like any other plant, carrots can be affected by pests and diseases. The main pest is the carrot fly and the main disease that affects carrots is carrot leaf blight.
Diseases that affect carrots
Like with most other plants, carrots are affected by blight, more specific by carrot leaf blight. This is a fungal disease which can be identified by dark brown, reddish marks on leaves and stems, with leaves withering on the tips.
Carrot leaf blight can weaken the plants and may stunt their growth, which could result in smaller carrots. In infected plants the stems might break during harvest, so it might be necessary to dig them out instead.
The fungus causing blight thrives in hot, wet conditions. There are things you can do to prevent blight affecting your carrots:
- Practice crop rotation, as the spores can overwinter in the soil. Only plant carrots in the same spot once every three years.
- To avoid the hot and wet conditions the disease thrives in, thin your plants out to give them increased air circulation and sunshine to allow the leaves to dry out quicker after rain.
- Water from underneath rather than overhead to keep the foliage as dry as possible.
If you spot any signs of blight on your carrots, remove the affected leaves immediately and weed around your plants regularly. Harvest your carrots as soon as they are ready.
As a root vegetable, carrots can also be affected by carrot scabs, a soil borne bacterial disease. It produces mycelium which affects the roots and therefore your crops.
As it only affects the roots, there are no signs above ground. Affected carrots will have dark, horizontal lesions on the surface, which can be raised or sunken.
Affected carrots are still edible, just peel them or cut away the bits with lesions on them.
The bacteria causing scabs love hot dry summers and also alkaline soil. Here are some things you can do to prevent carrot scabs:
- Don’t let the soil dry out, but at the same time don’t overwater your carrots as this will stunt their growth. You can put down mulch around your carrot plants to keep the soil from drying out.
- Don’t plant your carrots in alkaline soil. If you have no option, adjust the pH level of the soil by adding acidifying material, such as Sulphur Pallets. To find out the pH level of your soil, you can buy a DIY soil pH test kit to check your soil. The ideal pH level to avoid scabs is 5.2 or lower. Find out more about the importance of testing your soil in our article about how and why to test your soil.
- 【Premium Quality】: 100 test strips made of premium quality filter paper. Perfect for garden, outdoor & indoor plant soil quality testing.
- 【Fast & Accurate】: The test range of soil pH test strip is 0-14. Accurate and reliable test results can help you analyze the soil.
- 【Convenient Operation】: The first step is to use one tablespoon put 8 level tablespoons (4 ounces) of soil sample into a clean cup and mix it with 8 level tablespoons (4 ounces) of water for 30 seconds. The second step, let the soil water solution stand for 30 minutes until stratification occurs. The third step is to dip a PH test strip into the solution, keep the soil test strip in the solution for 3 seconds, and match the color plate with the color table after 1 minute.
- Important trace element gives ericaceous plants the ideal soil base for healthy growth
- Will gradually reduce the pH of your soil
- Avoid planting carrots in sandy soil, as this can also cause carrot scab.
- Practice crop rotation, using the same spot one in 3-4 years only. Include other root vegetables such as potatoes, parsnips, beetroots, etc.
Pests that affect carrots
One of the most common pests that affect carrots is the carrot fly, small black flies. Their larvae feed on the carrots and can make your entire crops inedible.
Despite its name, the carrot fly larvae also loves the roots of related plants, such as parsnips, celery and parsley. So if your carrots are affected, any related plants close are likely to also be affected.
The maggots tunnel into the carrots, which look rusty and black. If you break an affected carrot, you are likely to find slim, pale yellow maggots feasting on your crop.
Once your carrots are infected, there isn’t anything you can do. So the best option is to try and prevent the carrot fly to lay its eggs on your plants:
- When you sow you carrot seeds, sow them as thinly as possible, so that you don’t have to thin them out later. Because when you thin them out, the plants release a smell which will attract the female carrot fly.
- Confuse the carrot flies by planting your carrots amongst other plants, rather than all in one space. They are less likely to sniff out your carrots when they are mingled in with other plants.
- Even more effective, use the method of companion planting. While this is not a scientific method, it is used in organic growing to prevent pests and diseases. It uses the properties of one plant to help prevent pests and diseases in other plants. The ideal companion plants for carrots are plants of the allium family, such as onions, leeks or chives. Mix your carrot plants in with one or more of these plants and they will mask the smell of your carrots, keeping away the carrot flies.
- Start sowing your carrots later. The females start laying eggs in last spring, so sowing from mid-May/June onwards will avoid the first generation of carrot fly larvae. Carrot flies can produce up to three generations in one summer, so if you harvest before late August you will also avoid the second and potentially third generation.
- Again, practice crop rotation. The maggots can overwinter in the soil and then feast on the carrots you plant in spring. Remember to include parsnips, celery, celeriac and parsley in your crop rotation, as they are also affected by the carrot fly.
- Construct a barrier around your carrots to prevent the carrot fly from finding them. Carrot flies are low-flying insects, so a barrier, such as a fence made from horticultural fleece – around 90 cm (3 feet) high – will protect your carrots.
- Even better, if you have a balcony or an elevated patio area, grow your carrots in containers and place them there. The carrot flies won’t find them there.
- You can also cover your carrots with horticultural fleece once you have sown your seeds, such as Environmesh. This will keep the females from reaching your plants, even if they sniff them out.
Recommended Carrot Fly Protection:
- Agralan M571 Enviromesh Standard
- Assembly Parts
I have found this to be 100% effective at stopping the carrot fly.
I’ve tried the carrot fly resistant varieties but have had little success with them.
Aphids, another common garden pest, can also attack carrots. These sap-sucking insects will first appear on the underside of leaves and then progress to the rest of the plant. They extract nutrients from the plants in this way, but can also transmit viruses and diseases.
Most plants can tolerate a moderate number of aphids, but a large colony can hamper the growth of the affected plant. So here are some tips to deal with an aphid infestation:
- Tolerate aphids whenever possible and only act when the infestation becomes severe
- Ants tend to ‘farm’ aphids as they eat the honeydew the aphids excrete. They will protect their ‘livestock’ by removing predators. Ants are a sign of a heavy infestation.
- Encourage natural aphid predators to your garden, such as ladybirds, ground beetles, hoverflies, wasps and earwigs by planting nettles, marigolds, sedums, foxgloves or similar plants.
- You can remove aphids by hand, crushing them as you go. Or carefully shake the plants, catching the dropping aphids on paper. Move them to a part of the garden where they can’t do any harm if possible.
- A heavy infestation can be treated with soapy water. Simply mix a couple of drops of washing up liquid in a litre of water and spray the plants with it. Repeat for about five days to get rid of the aphids.
- You can also buy commercial horticultural soap. I have used Horticultural Gentle Liquid Soap with Neem Oil before and it worked well.
- Pure organic cold pressed neem oil concentrate unrefined one 1000ml bottle
- Gentle biodegradable liquid soap derived from plant oils one 1000ml bottle
- Combine together with water to form a neem spray or drench
Another pest that might be interested in your carrots are wireworms. They are the larvae of click beetles which feed on roots. Only three of the over 70 species in the UK will damage garden vegetables.
You won’t see any symptoms above ground, but the wireworms – thin, yellow-brown larvae with three pairs of small legs on the head end – will tunnel into the carrots leaving black edges around the entry point.
The signs can be mistaken for a carrot fly infestation. But if you see the culprit, you can easily distinguish them.
Small numbers will not impact on your crop, they are still edible, just cut away the affected bits.
Wireworms occur most likely in areas that have been recently converted from grassy areas. There are some things you can do to protect your carrots from wireworms:
- Cultivate the soil after harvest – turn over the soil to expose larvae to predators. As adult click beetles prefer to lay their eggs in grassy areas, they will decline when the soil is cultivated within two years of cultivation.
- Encourage natural predators of wireworms, such as birds, wasps, hedgehogs and ground beetles.
- Grow your carrots in containers, as click beetles are unlikely to lay their eggs in containers.
- Remove any wireworms from the soil if you spot them.
Frequently Asked Questions
Didn’t find what you were looking for? Find out more about growing tomatoes in our FAQ section.
Can you regrow carrots from carrot tops?
Yes, however, you can only regrow the carrot plant as in the green part, not the actual carrot.
Did you know that you can eat the green leaves of the carrot plant? It’s not only delicious, but also full of vitamins and minerals. There is an urban myth going around that carrot greens are poisonous, but that is just not true.
There are a lot of things you can do with the greens:
- Saute them in a pan with some oil with other greens
- Blanche them in water with other vegetables
- Add them to your soup or stock
- Make a carrot top pesto with them
So now that you know what to do with the greens, how do you re-grow them from carrot tops? It’s simple really. There are three methods, but by far the easiest is re-growing in water.
Just cut off the top of a supermarket bought carrot, about 2.5cm (1 inch). Fill a small glass with water. Don’t use a glass you want to re-use later, as it might get mineral stains.
Then insert a wooden toothpick into each side of the carrot top and put it into the glass of water. The toothpicks will keep the top balanced on top of the glass, allowing the stump to slightly touch the water.
Place the glass in a light place, but out of direct sunlight and keep the water level the same. Soon roots will start to sprout from the bottom of the carrot top. At this point you can transplant the stump in soil to grow a health plant.
Carrot plants will eventually produce lovely white flowers, so they are great as ornamental plants too.
How do I best store my freshly harvested carrots?
You can leave your carrots in the ground until you need them. Just over them with a layer of straw, mulch, cardboard or bracken and fix it with some netting or horticultural fleece. Protected in such a way, they should keep until March of the next year.
However, if you are living in a cold region (with prolonged subzero temperatures), you are better off storing your carrots indoors. Equally, if you live in a region that has very mild winters, where the temperatures are not low enough to keep the carrots from growing, you should also consider to store indoors. If the carrots keep growing they will become woody and tough.
Also, leaving your carrots in the ground could risk pests and diseases getting to them.
First, make sure you only store carrots that are in perfect condition and not damaged in any way. Ones that might look a bit odd or damaged, you best eat fresh.
Root vegetables like carrots, swedes, beetroot and celeriac will lose moisture if not stored correctly, which cause them to shrivel up. So you have to store them in a moist environment. There are two options:
Storing your carrots in the fridge
Small quantities can easily be stored in the fridge, as long as you have the space.
Ideal storing condition for carrots in a fridge is just above 0°C and they need 95% humidity. Mine, and most probably your fridge will be warmer and also drier than this. But if you prepare your freshly harvested carrots in the right way, you can still store them for 2-3 months in your fridge.
Here is how to prepare them:
- Don’t wash the carrots, just shake off most of the soil. It might sound odd, but leaving on some soil will help to prevent them from rotting.
- Leave them out to dry for several hours, but no longer than half a day, ideally in the sun.
- Cut off the green top close to the root.
Then put your carrots in a single layer in a zipped freezer bag then seal the bag, removing all the air. Store them in the vegetable drawer or on the shelf. This method should keep them fresh for a minimum of one month and up to 2-3 months.
Storing carrots in a box
Prepare your carrots as mentioned above. Get a box and put a layer of about 5 cm (1 inch) of moist sand in it and layer your carrots on top. Add more moist sand and keep layering until you have buried all your crops in the sand.
Then place the box, or boxes, in a cool, dark place such as a shed or cellar. Make sure you keep the location frost free, as frost can damage the root vegetables.
Check on your carrots from time to time to make sure the sand hasn’t dried out to avoid your carrots from shrivelling up. This method will keep your carrots fresh for up to 6 months, depending on how close you can get to just above 0°C and 95% humidity.
Can I grow carrots in containers?
The short answer is yes, you can grow carrots in containers. But you have to use the right container, because carrots grow down, you need a good depth.
Before we moved to a house with a big garden, I used these carrot planter bags and they were great.
- No digging required
- Designed to be easy to use
- Quality product from Haxnicks
And once you have finished you can just clean them and store them away easily.
Whichever container you choose, make sure you have a depth of around 30cm and drainage holes. To ensure your drainage holes won’t get blacked by the soil, start off with a lawyer of gravel.
Then add your compost. You can use a mix of compost and sand (50/50), which will help with drainage and will also make the soil lighter, which will help the carrots to grow straight.
Lay a thin layer of compost on top and then add your seeds, followed by another thin layer of compost. Water and look forward to the seedlings appearing.
Soil in containers will dry out quicker than in the ground, so you need to make sure you water your carrots regularly to keep the soil moist, but not wet.
There are some varieties that grow better in containers than others, such as Chantenay, Oxheart or Round carrots as they are shorter.
Why didn’t my carrot seeds germinate?
The first reason could be that the seeds were planted in soil that was too cold. While carrots need cool temperatures to germinate, the soil shouldn’t be below 7°C. The ideal germination temperature for carrot seeds is 10°C, which should cause them to germinate within 10 days.
Another reason could be that the seeds were planted too deep. Plant your carrot seeds about 2cm deep to ensure they germinate.
Seeds also rot if they are too wet, so make sure that you don’t overwater them.