How to Plant Carrot Seeds

By
Barbara Gillette
Barbara Gillette
Barbara Gillette
Barbara Gillette is a master gardener, herbalist, beekeeper, and journalist. She has 30 years of experience propagating and growing fruits, vegetables, herbs, and ornamentals.
Learn more about The Spruce's Editorial Process
Published on 03/15/23
Carrot Seeds

HeikeRau / Getty Images

Project Overview
  • Working Time: 1 hr, 30 mins - 2 hrs
  • Skill Level: Beginner
  • Estimated Cost: $3 to $10

Carrot seeds are tiny, about the size of the tip of a sharpened pencil. Unless you have hours to spend, they are impossible to evenly space, one by one, in straight rows. It's more efficient to broadcast seed, either in rows, a planting bed, or thin plants once tops are 3 to 4 inches tall. Carrots are easy to grow, a fun garden project for kids, and delicious to eat fresh and cooked.

When Should You Plant Carrot Seeds?

Carrots are considered a cool season crop. Seeds germinate most reliably when soil temperatures reach 55 degrees Fahrenheit. However, they will continue to sprout up to 75 degrees which makes them an excellent choice for succession sowing. In most growing zones, seeds are planted two to three weeks before the final frost and again every three weeks until mid-summer. In growing zones with milder winters, carrot seeds are also sown in autumn 8 to 10 weeks before the first frost.

Before Getting Started

Carrots grow best in sandy, loamy soil with a pH of 6.0 to 7.0. Clumpy soil, rocks, and debris cause them to split, so taking the time to prepare the garden bed is important. Work up the planting area to about a foot deep, adding sand or well-aged compost until you've created a light, fluffy loam. A good combination is two parts sand and one part compost to one part soil.

If you'd like to grow carrots in pots, choose a large container at least 12 inches deep. Fill it with a light potting medium or add sand and compost to regular garden soil. Avoid mixes with added fertilizer which may contain too much nitrogen for growing carrots.

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What You'll Need

Equipment / Tools

  • Garden hoe
  • Garden rake

Materials

  • Carrot seed
  • Sand
  • Radish seeds (optional)
  • Garden marker

Instructions

  1. Label the Planting Bed

    Label the planting area with a garden marker. Carrot seeds take between two and three weeks to germinate. Sowing carrot and radish seeds together is another way to identify your carrot patch. Radishes germinate quickly to mark the bed and are harvested before carrots need the space.

    Tip

    A planting bed for carrots is usually a small square, rectangle, or circle of soil set aside and marked for growing the crop. Carrots also are grown in raised beds.

  2. Make Shallow Furrows

    If growing in rows make shallow furrows 1/4 inch deep and 12 inches apart. Seeds cannot break through crusted soil, so a soft top surface is essential for germination. Use a rake to loosen it in a planting bed.

  3. Mix Carrot Seed With Sand

    Mix the carrot seed packet with about four times as much sand. Measurements don't need to be perfect. Sand helps separate and spread out the tiny seeds for the best chance of even spacing. For growing in pots, sand is optional.

  4. Broadcast the Seed Mix

    Take a small handful of seed mix and shake your hand back and forth across the seed bed or down the row, scattering the seed and sand as you go.

    Then, change direction and continue the motion until all the mix is used. If you're using a pot, scatter the seeds as evenly as possible or take a small pinch and feather seeds onto the potting soil.

  5. Cover Lightly

    Carrot seeds need light to germinate, so use a garden rake to lightly cover them with soil, about 1/8 inch. For seeds started in containers, sprinkle potting mix across the soil surface.

  6. Water Gently

    Use a gentle spray setting on your hose nozzle, or a watering can with a rose spout to moisten the planting area. Keep the soil moist until germination occurs in 14 to 21 days.

  7. Fertilize and Water

    Fertilize your carrot crop about six weeks after the green growth first appears. Use an NPK lower in nitrogen, like a 0-5-5, or 5-10-10. Too much nitrogen promotes leafy top growth at the expense of the root.

    Carrots need about 1 inch of water per week. Drip hose irrigation works best but overhead watering is okay provided the crop is kept free of weeds.

  8. Thin Seedlings

    Carrots need about 3 inches of space each to grow well. Seeds don't germinate all at once so thinning is essential and should be done regularly when tops reach about 3 to 4 inches tall.

  9. Consider Mulching

    Adding a natural mulch like straw or grass clippings is optional but improves moisture retention. For carrots grown in autumn, mulch can extend the season by protecting roots from freezing temperatures.

  10. Harvest the Carrots

    Depending on the variety, carrots are harvested 55 to 70 days after sowing seed. They can be harvested any time they reach edible size but root tops 3/4 inch in diameter are a good size. It's easier to remove carrots when the soil is slightly dry. Digging with a small shovel or garden fork is the best way to avoid root breakage and damage.

FAQ
  • How many carrot seeds should I plant in one hole?

    Due to their small size, it's more efficient to plant carrot seeds in furrows or planting beds instead of planting holes. If growing in containers, sprinkle seed on the surface and lightly cover with potting mix.

  • Should I soak carrot seeds before planting?

    Soaking is an option and may speed up germination. Cover seeds with cold water for 24 hours, then wrap them in a paper towel and place it in a closed container for two or three days before planting out.

  • Can you just scatter carrot seeds?

    Broadcast or scatter sowing is a common method for planting carrot seeds. The seed should be very lightly covered with about 1/8 inch of loose soil. Be sure to mark your row or bed before planting. Carrot seeds can take up to three weeks to germinate.