How I Grow Carrots in Containers (from Seed to Harvest)

Growing carrots in containers is an easy and space-saving way to enjoy fresh, homegrown produce. 

Use a container with drainage holes and a depth of at least 30 cm / 12 inches. Carrots need room for their roots to grow, and proper drainage is vital to keep the roots from becoming waterlogged. Containers from materials like plastic, terra cotta, wood, and fabric grow bags work well.

Fill your container with a loose, well-draining soil mix. A blend of high-quality potting soil and aged compost provides an ideal environment for carrot growth. Leave about 3 cm / 1 inch of space at the top of your container for easier watering.

Prepare the bed using a tiller or garden fork to loosen the soil before planting. 

Space the carrot seeds about 3 cm / 1 inch apart in the soil. Planting the seeds too densely will force the carrots to compete for resources, resulting in smaller roots. 

Carrot seeds have a good germination rate, often around 70%, and soaking the seeds in water for a few hours before planting can further promote germination.

Plant the seeds in pre-moistened soil about 1 cm / 0,4 inches deep, cover lightly with soil, and water gently. Expect seeds to germinate in about 10-20 days.

Place the container in a location with at least six hours of sun daily. Monitor the soil moisture, and water your carrots regularly, maintaining even soil moisture. Overwatering or underwatering can cause the roots to crack, become fibrous, and even rot.

Thin the carrot seedlings to maintain 3-5 cm / 1-2 inches between the plants. Carrots typically mature within 70 to 90 days and can be harvested once they reach 1,5 cm / 0,5 inch in diameter. 

Why I Grow Carrots in Containers

Carrots grow well in containers, and there are several benefits compared to growing carrots in garden beds.

Full control of soil

Carrots want loosely structured, fertile, well-draining soil to promote healthy root growth. And using containers, I can ensure that I give my carrots the best possible growing environment free from stones, soil clumps, and other hard objects. 

Efficient use of space

Containers are a great way to grow carrots with limited space. Perfect for balconies or patios, but also for home gardeners where available space often becomes an issue.

Flexible

Container gardening is flexible, making it easy to move or cover the container as needed. 

Stagger planting at three-week intervals to prolong the harvest. 

Common Mistakes to Avoid Growing Carrots in Containers

Choosing the Wrong Container

Carrots grow deep; you need a deep container to accommodate their long taproots. Ensure the container is at least 30 cm / 12 inches deep and comes with proper drainage holes to prevent waterlogging.

Overcrowding

Carrot seeds often come in packages with hundreds of seeds, and it is easy to scatter the seed across the soil.

But planting too densely and overcrowding will stunt carrot growth, and your yield will suffer.

Plant 3-5 carrot seeds in each hole, spacing the holes about 3 cm / 1 inch apart. 

Thin seedlings later as needed, keeping only the strongest plants. I thin out seedlings when they have reached 5-8 cm / 2-3 inches in height.

Thinning out may seem wasteful, but it is essential as it gives the carrots room to grow.

Not Providing Enough Sunlight

Carrots require at least six hours of sunlight per day to grow properly. 

Place your containers in a location that receives sufficient sunlight. If you live in an area with limited sunlight, move containers to maximize available sunlight or supplement natural light with grow lights.

Poor Soil Quality

Using the wrong soil mix can lead to slow growth, small roots, or even all foliage with no roots to harvest. 

Use fertile, well-draining soil mix rich in organic matter. A mix of equal parts soil mix, compost, and perlite is a good choice for container-grown carrots.

Watering Inconsistently

Carrots need even soil moisture to grow and thrive. 

Overwatering can lead to root rot and non-existing roots. Underwatering will stunt growth and leave you with a poor yield. 

Water your carrots regularly, and always feel the soil before you water. 

Timing

Carrots are best planted in early spring for a summer harvest or fall for harvesting the following spring. 

Choosing the Right Container

Choosing the right type of container is key when growing carrots in containers— factors to consider: Drainage Holes, Depth, and Shape.

Drainage Holes

Ensure the containers you use have sufficient drainage holes at the bottom. 

Drainage holes prevent excess water from accumulating at the bottom of the pot, leaving the roots in constant wet. 

Use a tray or saucer underneath the container to collect excess water to protect your surfaces.

Depth

I use square or round bucket-type containers with a 30 cm / 12 inches depth. I have found this depth to accommodate most types of carrots.

Check the plant information on the seed packet. There are carrot varieties that grow very long roots and that are less suitable for container gardening. 

Shape and Pots vs. Planters

You want a square or cylindrical shape container for carrots. Avoid using containers that are wide on top and narrow at the bottom. 

As for pots vs. planters, it comes down to personal preferences and available space. 

• Pots: Suitable for growing a smaller number of carrots, available in various materials (such as plastic, terra cotta, and ceramics), and come in different sizes and shapes.
• Planters: Ideal for growing a larger number of carrots, typically rectangular or square, and made from materials like wood, plastic, or metal sheets.

Selecting a Suitable Carrot Variety

You can grow any carrot in a container, but given the option, choose a short, round, or cylindrical variety that will thrive in a limited space. 

Short and Round Varieties 

Short and round varieties are perfect for container gardening with their compact size, and they will happily adapt to less spacious conditions. Ideal in containers less than 30 cm / 12 inches deep. 

I am growing a Parisian variety this year, but there are many more to choose from. Parisian carrot varieties develop smaller, round roots up to 5 cm / 2 inches in diameter.

Cylindrical Carrot Varieties 

Cylindrical Carrot Varieties form more traditionally shaped roots and need deep-enough containers for their growth. Choose a variety that develops medium-sized roots between 10-15 cm / 4-6 inches for best results. 

This year I am growing F1 Aron carrots that can be harvested as mini-carrots or grown to full size of 10 cm / 4 inches. The roots are cone-shaped and tubby-looking.

Consider the depth and size of your container when selecting your carrot variety. Prioritize providing ample space for root growth, and ensure proper care to yield a successful harvest in your container garden.

Preparing the Soil

Selecting Soil Mix

Use fertile, well-draining potting soil mixed with compost and perlite or coarse sand to promote drainage. 

Carrots require even soil moisture; amendments like vermiculite can help promote soil aeration and retention. 

Peat moss is a popular soil amendment, but I no longer use it because of sustainability issues, and it is easy to find suitable alternatives. 

Adding Nutrients

Add rich, organic matter like compost to help your carrots grow and thrive. For overall soil health, consider adding the following soil amendments:

• Compost: improves its fertility and texture
• Vermiculite: retains moisture and enhances soil aeration
• Perlite or Sand: improves drainage and prevents the soil from becoming compacted
• Organic fertilizers: enhances nutrient content and promote root development

Impact of Soil Type

Loose, well-draining soil allows carrots to form roots with minimal resistance. Heavy clay or compacted soils hinder root development, resulting in misshapen and stunted carrots.

Loosen the soil using a tiller 30 cm / 15 inches deep for best results.

Planting Seeds

Depth and Spacing

Plant the seeds in pre-moistened soil about 1 cm / 0,4 inches deep, cover lightly with soil, and water gently. 

Place 3-5 seeds in each hole with a 3 cm / 1-inch spacing between the holes. 

Carrot seeds have a good germination rate, often around 70%.

If you are worried about germination, soak the seeds in water for a few hours before planting to promote germination.

Planting the seeds too densely will force the carrots to compete for resources, resulting in smaller roots. 

Expect seeds to germinate in about 10-20 days.

Temperature and Germination

Carrot seeds germinate from 5 degrees Celcius / 40 degrees Fahrenheit and will even overwinter in freezing temperatures.

Carrots are one of my favorites for winter sowing and thrive in the shoulder seasons - April to June and October-November.

Carrots thrive in cooler weather, with an optimal temperature of around 16-18 degrees Celcius / 60-65 degrees Fahrenheit.

Keep soil evenly moist but not wet during the germination process. 

Depending on the temperature and moisture conditions, the seeds usually take 10-20 days to germinate.

Timing of Planting

Plant seeds about 2-4 weeks before your region’s last expected frost date. 

You want to plant this early to give the seedlings time to establish themselves before the warmer weather arrives.

Carrots thrive in the shoulder seasons – April to June and October-November. Stagger plantings of carrots at three-week intervals as the soil temperatures rise for continued harvest throughout the season.

Staggered planting lets you harvest continuously without having too much produce at any one given time. Growing lettuce in soil bags is another great use of this technique.  

Caring for Growing Carrots

Watering and Moisture

Carrots need even soil moisture for proper growth. 

Water regularly, but avoid overwatering as it can lead to root rot and cracked carrots. 

An alternative is to use a drip irrigation system or soaker hose in your container for a relatively hands-off method to ensure constant soil moisture.

I prefer using a soil moisture meter and taking a quick reading before I water.

Remember to factor in rainfall if your containers are exposed to the weather. 

Light Requirements

Carrots will grow best in full sun, and you should place your container in an area that receives a minimum of 6 hours of direct sunlight daily. 

From my experience, locations with partial shade work fine for growing carrots as long as the container gets at least 6 hours of sunlight during the day. 

Weeding and Mulching

Container gardening makes it a lot easier to control weeds. Still, weed regularly and remove anything competing for nutrients and space. 

Applying a layer of mulch can help suppress weed growth and help retain soil moisture. 

Feeding and Fertilizing

Carrots are heavy feeders and require nutrients to grow and thrive. 

When planting, I prepare my soil with compost and organic fertilizer with balanced nitrogen, potassium, and phosphorus levels. 

As seedlings are established, I switch to a more potassium and phosphorus-heavy fertilizer.

I typically fertilize my carrots once or twice during the growing season.

Using high-nitrogen fertilizers can lead to excessive foliage growth at the expense of root development. 

Managing Pests and Diseases

Common Pests

Like all vegetables, carrots are susceptible to pests and diseases.

Some common pests include caterpillars, the carrot rust fly, and aphids. [1]

Personally, I have never had pests or diseases ruin my carrot harvest. I follow the simple steps below, and I have never had any issues to date.

• Protect your plants with row covers as long as possible
• When seedlings are established, mulch the bed
• Inspect plants manually and remove pests like aphids when spotted
• Let some herbs and plants bloom to attract beneficial insects like ladybugs

Common sense tip: We grow carrots for the root. We should primarily focus on soil-dwelling pests and larvae. Covering your plants before they are established will protect the soil from pests laying eggs in the soil and damaging your roots as they hatch into larvae.

Disease Prevention

My best tips to minimize the risk of pests and diseases are:

1. Cover your plants for as long as possible
2. Ensure proper drainage to prevent root rot and fungal diseases
3. Consider planting disease-resistant carrot varieties 
4. Ensure proper spacing between plants to promote airflow

If your container-grown carrot roots become infected with diseases, isolate the infected plants and discard infected plants to prevent further spread.

If you suspect the disease has affected your container soil, replace the soil before planting another crop in the same container.

How to thin out carrot seedlings

Carrot roots need space and resources to grow and thrive. As the carrot seedlings get established, you should thin them out to avoid overcrowding:

1. Wait until seedlings reach a height of 5 cm / 2 inches.
2. Identify the stronger, healthier-looking seedling to keep.
3. Gently cut the weaker seedlings just above the soil level without disturbing the remaining ones. Aim for a final spacing of 3-5 cm / 1-2 inches between seedlings.

Always thin out the seedlings by cutting the weaker seedlings. Pulling the seedlings will risk disturbing the root system of the stronger seedling.

Why you should not transplant carrot seedlings

Transplanting carrot seedlings is a hit-or-miss endeavor at best. Carrots develop delicate root systems that are very sensitive to disturbance. 

Transplanting carrot seedlings may feel like a win-win situation – but this is not entirely true. 

Sure, if you are successful, you have one more plant. And if the transplanted seedling dies, you could argue that you were going to thin it out anyway.

But there is also a real risk of losing all the seedlings, including the stronger one you planned to keep. 

But if you must transplant carrot seedlings, follow the steps below:

1. Prepare the receiving container or garden bed with loose, well-draining soil.
2. Carefully remove the seedlings with minimal root disruption.
3. Transplant seedlings at the same depth as in their original container while maintaining proper spacing.

Harvesting and Storing Carrots

When to Harvest

I harvest my carrots when they reach a diameter of about 1,5 cm / 0,5 inches.

This typically occurs around 70 to 90 days after planting.

To check the level of maturity of your carrot roots, gently brush away mulch and soil and inspect the diameter of the root. 

Harvest Techniques

I use different picking techniques depending on how many carrots I harvest. 

If I harvest an entire container, I drench the bed with water. Next, I pull the carrot by grabbing the greens at the crown and gently tugging it with a twisting motion.

To harvest individual carrots, I start by loosening the soil around the base of the carrot with a garden fork. When the soil is loose, I grab the carrot greens close to the root and gently pull and wiggle the carrot back and forth to ease it out of the soil. 

As a rule, I leave carrots in the ground until needed. 

Storage Methods

I use most of the carrots I grow within a week of harvesting. But some are stored for longer, often at the time of year when the garden produces tomatoes, cucumbers, radishes, leafy greens, and eggplants in abundance.

Immediately after harvesting, remove the carrot greens to reduce moisture loss, and then brush the carrots clean and dry the roots with a cloth.

I store carrots for several weeks in the crisper drawer of our refrigerator. Place the carrots in a plastic bag and add a few holes for ventilation.

To freeze your carrots, blanch them for 2-3 minutes and then rinse them in cold water. Once cold, place carrots in airtight freezer bags and store them in the freezer. 

Frequently Asked Questions

What is the ideal container size for growing carrots?

A container with drainage holes and a depth of at least 30 cm / 12 inches is suitable for most varieties of carrots. 

How many carrots can be successfully grown in a single container?

It depends on the size of the container. Allow for 3-5 cm / 1-2 inches between plants to give you an idea.

Which soil mix is most suitable for container-grown carrots?

A well-draining, loose, fertile soil mix works best for container-grown carrots. 

Can I reuse the soil after harvesting the carrots?

Yes, but not for carrots and only after re-vitalizing the soil.

Carrots should be rotated and not planted in the same spot repeatedly. 

Use leftover soil in a compost pile LINK or mix with a balanced fertilizer and scatter in your garden.

Can carrots be grown indoors using containers?

Carrots can be grown indoors using containers with adequate sunlight (6-8 hours). 

Consider using grow lights if natural light is insufficient. For optimal growth, ensure the room temperature stays between 15-23 degrees Celsius / 60-75 degrees Fahrenheit.

How long does it take for carrots to mature when grown in pots?

Most carrot varieties take about 70-90 days from planting to harvest. 

Check progress by gently feeling the tops of the carrot roots near the soil line. When the diameter reaches your desired size, carefully harvest the carrots by gently pulling them out of the soil.

Can I use soilless potting mixes?

You can use soilless mixes to minimize the risk of diseases and pests, but they will require more frequent fertilizing for your carrots to grow and thrive. 

Helpful sources:

[1] https://content.ces.ncsu.edu/insect-and-related-pests-of-vegetables/pests-of-carrots