Carrots are biennial vegetables, though they are typically harvested in their first year of growth before they overwinter and set flowers the following year. Carrot foliage is finely dissected with fern-like compound leaves. Carrot flowers have five petals and sepals and are born in compound umbels. Most carrot roots are about one inch in diameter and anywhere from one inch to more than 12 inches long. Carrots are best known for long, orange roots, but they actually come in several colors and shapes.
Plant carrots in the spring and seeds will germinate in 10 to 21 days. From seed to harvest typically takes 50 to 75 days.
|Botanical Name||Daucus carota|
|Family||Apiaceae or Umbelliferae|
|Size||6 to 12 inch root, 1 foot foliage height; 9 inch spread|
|Sun Exposure||Full sun to part shade|
|Soil Type||Loose, well-draining soil|
|Soil pH||Slightly acidic (6.0–6.8)|
|Bloom Time||Spring (second growing season)|
|Hardiness Zones||3–10 (biennial grown as an annual)|
|Native Area||Europe, Southwestern Asia|
How to Plant Carrots
When to Plant
Carrots grow well in cool weather. You can begin planting carrot seedlings or sowing carrot seeds as soon as the soil can be worked in the spring, even two to three weeks before the last frost. You can succession plant carrots every couple of weeks throughout the spring. In warmer climates, you might have better luck growing carrots in the fall and through the winter.
Selecting a Site
Carrots will do well in a spot that's sunny six to eight hours a day or with a little shade in late afternoon. The soil should be loose, sandy, and well-drained because carrots will mature very slowly with rough roots if they are forced to grow in heavy soil. Growing carrots in raised beds with fluffy soil is the ideal situation.
Spacing, Depth, and Support
Correctly spacing carrots is the key to harvesting a healthy crop, but it's not always easy and requires plenty of thinning. Plant seeds 1/4 inch below the surface of the soil as evenly as possible two to three inches apart. Seedlings will be okay if some of them sprout 1/2 inch apart, but as they grow, they typically require about three inches of space between them. Snipping or pinching the seedlings off at the soil line is the best way to avoid hurting the nearby roots. Carrots don't need support; But, they don't like to be transplanted or disturbed, either.
Even though the roots are growing underground, the foliage needs full sun to partial shade for the carrot roots to grow quickly and develop their sugars.
Carrots need loose, well-draining soil. Rocks and clumps will cause the carrot roots to split and become deformed. Carrots prefer a slightly acidic soil—in the range of 6.0 to 6.8.
Water your carrots with at least one inch of water every week. Mulching will help conserve water and keep the soil cool.
Temperature and Humidity
These biennials are typically grown as annuals in all zones and in all climates. However, they grow best and are tastiest when nighttime temperatures average about 55 degrees Fahrenheit and daytime temperatures average 75 degrees Fahrenheit. In warmer climates, carrots are sometimes planted as a late fall and winter crop.
If your soil is not rich in organic matter, supplemental feeding will be necessary about two weeks after the carrot tops emerge. Any good quality organic vegetable fertilizer will do. Because they are grown for their roots, don't go overboard with nitrogen fertilizer, which mostly aids foliage growth
Types of Carrots
There is a seemingly endless number of carrot varieties in an array of sizes and colors. Some notable varieties to try include:
- 'Danver's Half Long': early, sweet, and easy growing
- 'Imperator': a long variety that keeps its sweetness and crunch in storage
- 'Little Finger': a sweet three-inch baby carrot
- 'Paris Market'/'Thumbelina': plump, round, and bite-sized
Carrots vs. Parsnips
Carrots can often be confused with parsnips. That's because not all carrots are orange, and many types of carrots and parsnips are the same color and shape. Carrots and parsnips (Pastinaca sativa) also share the same family. The biggest difference between the two is their taste; Carrots are sweet and parsnips have a spicy bite. Often they are both used in the same recipe to bring full flavor to a dish.
Growing carrots (Daucus carota)—or any root vegetable, for that matter—can be a bit of a gamble because you can't see how well they're doing until you harvest. When to harvest your carrots will depend on the variety you are growing, but the average days to harvest is about 50 to 75 days from seed.
Use the days to harvest on your seed packet as a guide to know when to start harvesting. Test to see if the tops of your carrot plants have filled out to the expected diameter by feeling just below the soil line. The only true test is to lift one of the carrots and taste it.
Don't harvest too soon, thinking you will get sweet baby carrots. Small carrots in the store are either a particular variety that matures small or large carrots that have been ground down to baby-size. Immature carrots will be bland because they have not had time to develop their full sweetness. Often sweetness develops when the crop has been through a frost.
If the soil is very soft, you can twist and pull the carrots from the soil. To be on the safe side, it is wise to loosen the soil slightly before harvesting, making sure not to stab the carrots in the process. Remove the leaves immediately after harvesting. The leaves will continue to take energy and moisture from the roots, leaving them limp, and lessening the sweetness of your carrots.
How to Grow Carrots in Pots
Carrots require loose well-drained soil. They will fork and deform if they meet with the slightest resistance, such as a rock or hard soil in the garden. If you can't provide loose soil in your vegetable garden, consider growing carrots in a container using potting soil premixed especially for potted vegetables. The shorter finger-types or small round carrots, like 'Paris Market', or other types with roots that grow and mature to two to three inches long, are ideal for containers.
Make sure your container (any material is fine) is at least 12 to 24 inches in diameter, at least 12 inches deep, and with plenty of drainage holes. Container carrots will require more water than crops in the ground; Water the container deeply once a week.
To prevent deformed roots, keep the area free of weeds as the carrots are growing. If you need to thin them again later, you can use the tiny carrots in salads. When you've finished thinning, your carrots should be far enough apart so they don't rub shoulders when mature.
How to Plant Carrots From Seed
Carrots can be planted from nursery-grown seedlings, but the more common method is to sow seeds directly into the garden as soon as the soil is workable in the spring. But, carrot seeds are tiny making it difficult to plant them evenly. They may take as long as three weeks to sprout.
- Till the soil at least a foot deep to make sure it is light and loose and can drain extremely well.
- Create shallow furrows in the soil (the long handle of a garden tool will do the job), 1/4 inch deep and one foot apart if you are sowing more than one row of carrots.
- Sprinkle the tiny carrot seeds two to three inches apart, 1/4 inch deep, and cover lightly with soil. It's difficult to space carrot seeds evenly, so you will likely need to thin them out as they grow.
- Write the crop name and date sown on a plastic row marker, paint stick, or popsicle stick to mark the location of your seeded row(s). Marking the location of the rows helps you know where to water.
- Press down lightly on the soil to ensure good contact between seeds and soil.
- Keep furrows moist and don't let the soil dry out because it will form a hard crust that is difficult for tiny seedlings to break through.
- Give seedlings one inch of water per week.
- When the seedlings are one to two inches tall, thin them then out to be three inches apart. Use tiny snips for this task so you don't pull up nearby developing carrot roots.
You can leave carrot plants in place over the winter. Make sure you thoroughly weed the area before the first frost. Heavily mulch the area with about three inches of straw or fallen leaves. You might even consider installing a fabric row cover if you live in a very cold climate. The carrot tops will die but the roots will continue gathering their sugar to survive the cold weather. Even if left in the ground into winter, the roots can still be quite delicious. Harvest these carrots before the early spring arrives or they will start to form flowers.
Common Pests and Plant Diseases
The biggest pest that attacks carrots is the carrot rust fly. It lays its eggs in the soil near the carrot top. When the eggs hatch, the larvae work their way down into the soil and then into the carrot's roots, where they feed and create tunnels through the carrot. Carrot weevils can do similar damage. You can foil some pests by rotating where you plant each year, but the easiest method is to grow your carrots under row covers (garden fabric).
Nematodes, microscopic worms, can become a problem later in the season, causing badly deformed roots. Heating the soil through solarization can kill nematodes. If you are struggling with carrot nematodes in a particular spot, rotate to another crop and plant carrots elsewhere.
Even if they don't notice the roots growing below the soil surface, there are plenty of animals that will want to eat the tops of your carrots and a few that will dig deeper. Deer, groundhogs, rabbits, opossum, and several others will need to be kept out of the garden—fencing is really the only effective method.
A handful of leaf spot and bacterial diseases can affect carrots, like Alternaria leaf blight, carrot yellows, and bacterial soft rot. There is not much you can do once the plants are infected. Keep a close watch and remove any plants showing signs of disease. Clean up all debris at the end of the season and move your carrots to a different section of the garden next year because the microorganisms can persist in the soil.
Are carrots easy to grow?
Even experienced gardeners can be challenged to growing carrots that are long and sweet. Very often, carrots can disappoint with bland, misshapen, tough roots. But given loose soil, some cool weather, and plenty of water, there's no reason you can't grow sweet, crunchy carrots.
What is a good companion plant for carrots?
To prevent the soil from crusting over and making it difficult for carrot seeds to sprout, plant the carrot seeds with radish seeds, which will sprout first and loosen the soil.
Can you grow carrots in water?
Yes, and no; A carrot is a taproot that can't regrow itself. But there is a fun, entertaining project for kids involving putting the top stump of a carrot in a glass of water, held by toothpicks much as you would do with an avocado pit, and watching carrot roots grow in the water.
Utah State University. “Carrot Rust Fly.” Usu.Edu.
“Carrot Leaf Blight Diseases and Their Management.” Cornell.Edu.