Garden Doctors: How to grow carrots

Susan R. of Santa Rosa asks: I love carrots and have tried several times to grow my own, but with no success. Can you provide some growing tips and any secrets to growing sweet, delicious carrots?

First, carrots are usually classified by their root shape: (there are 4 that are commonly available)

Chantenay – these are shorter than other types, are stocky, taper to a rounded tip, and have a rich, sweet flavor that are good for storage. They are coarser in texture than other carrot types.

Danvers – Shorter than the Imperator varieties, with a thick-rooted cylindrical shape, widely used in processing, good for juicing, and stores well. Performs well in heavy, clay soil.

Imperator – Have long, tapered roots with stocky shoulders and strong tops and a slightly fibrous texture. Stores well. This is the most common type found in grocery stores. Prefers deep, sandy soil.

Nantes – Blunt tips, with straight, cylindrical roots 5 to 7 inches long that are sweeter than most other types that are delicious when eaten raw. Prefers loose soil.

Carrots do best in fertile sandy loam soil, but will grow well under most conditions if you choose the appropriate variety. For heavy, compact soils, choose the tapered carrots that can work their way into soils like the Chantenays or Danvers types. A little potassium incorporated into the soil promotes solid, sweet carrots.

The ideal soil temperature for seed germination is 55-75°F. You’ll get the highest rate of germination from seeds sown in raised beds, with a sandy loam soli free of stones and debris. The Imperator type carrots should only be grown in raised beds that are at least 10-12” in depth.

Full sun is a must for carrots. Direct seed ¼ to ½ inch deep as soon as soil can be worked in the spring through mid-summer. Weeding shortly after the seeds germinate allows slow-growing carrots to get a head start against those fast-growing weeds. After that, thin the seedlings 1” to 2” apart, depending on the desired size you want. For early small bunching: ~45 seeds/ft; For full size ~30 seeds/ft; For soup size or storage ~15 seeds/ft. If you should miss the opportunity to pull weeds when they are small, use scissors and cut them off at the base. Do not pull them out as you could also pull up the carrots!

Prolonged hot weather and insufficient water may stunt growth, and a strong flavor and coarseness in the roots. Putting shade cloth over them during the hottest part of the day might help.

Harvest the carrots when have reached their color, size, and their flavor has developed. Push a little soil away from the tops and you’ll be able to see about how big or little the carrots are. Young carrots. also called baby carrots, are also very delicious at this stage. Carrots hold up well in the soil for up to 3 weeks in the summer and longer when it’s cooler. Some varieties can be over wintered outdoors or in a coldframe or high tunnel for an early spring harvest

If you want to store your carrots, cut off the tops and keep them in near freezing temperatures with high humidity. Unwashed carrots store just as well as washed carrots.

Carrot Weevil and carrot rust fly are common pests. Place a floating row cover over the seedlings to help provide some control. You could also delay sowing seeds until June to avoid the first wave of flies, as well as sowing carrots seeds thinly, as the carrot rust flies are attracted to the smell of bruised carrot foliage.

Misshapen Roots – In general, carrots do not grow well in heavy soils. The long-rooted varieties such as the Imperator types may be twisted, stunted or forked when grown in this type of soil, or when they touch clumps or rocks. If you have a heavy soil, mix in compost to loosen the soil or grow the shorter varieties, such as Danvers types.

Greenish Shoulders – When the tops of the carrots are exposed to sunlight, that exposed top will often turn green. To prevent this from happening, cover the tops of the carrots with additional compost or soil.

Dana Lozano and Gwen Kilchherr are garden consultants. Send your gardening questions to The Garden Doctors, at pdgardendoctor@gmail.com. The Garden Doctors can answer questions only through their column, which appears twice a month in the newspaper and online at pressdemocrat.com.