How to Grow Carrots
Carrots come in four basic types: Imperator, Danvers, Nantes and Chantenay. Imperator types are long and tapered with a bright orange exterior and are most often sold in bunches as fresh market carrots. Nantes are shorter with a bright orange color, blunt tip and cylindrical shape. Nantes are known for their crisp texture, sweet flavor and overall high quality. Danvers are shorter than Imperator with a similar tapered shape. Danvers carrots tolerate heavy soils, store well, and can be used for fresh consumption or processing. Chantenay carrots are the shortest of all, with medium to bright orange exteriors and broad shoulders leading to a tapered tip. These carrots are excellent keepers and are most often used for processing and storage. You may consider growing and comparing all types initially to gain an understanding of which grow best in your soil and which you like best.
Add generous amounts of compost or other organic matter to your soil. If you use manure, make certain it is well rotted, because fresh manure with relatively high levels of nitrogen will result in deformed carrots with rough, hairy exteriors. Carrots grow well in a pH range from 5.5 to 7.0. If you are concerned about the depth of your soil, consider growing in raised beds where the elevated soil will provide the qualities needed for superior carrot production.
Carrots grow best when temperatures are moderate, between 59 and 65 degrees F. Higher temperatures may result in poor flavor and shorter roots. A steady supply of water is also necessary for top quality carrots and highest yields. Succession planting every three weeks keeps a fresh supply. You can begin sowing seeds as soon as the soil can be worked and continue until mid-summer. Carrots can withstand light frost at either end of the growing cycle.
Carrots are almost always direct sown. The seeds are small and often end up being sown in too great a concentration which requires thinning after they have germinated. To eliminate this time consuming task, commercial growers use mechanical seeders which regulate the flow of seeds. Pelleted seeds are also available, which in combination with a mechanical seeder give precise control over planting distance and eliminates wasted seed. Carrots are typically sown 3/4" - 1" apart in 2" wide rows 16-24" apart, or in single rows 15-30" apart. Plant to a depth of 1/4 - 1/2" and irrigate regularly to keep the soil from crusting before the seeds germinate. Crusting will impede germination and result in an uneven stand. If you are growing small quantities and concerned about maintaining a regular watering schedule during the crucial germination period (which can last up to three weeks), consider covering your seeds with a 2 x 4 or cardboard for the first week after you have watered. Some people mix radish seeds in with their carrots to mark the rows. Once the carrots are up, thin so they are 2-3" apart in the row.
Carrots don't compete well with weeds and can be set back by cultivation, especially near the top of the roots. Mulching will relieve you of careful hand weeding and prevent the shoulders of the carrots from turning green.
Carrots are usually ready to harvest 60-70 days after planting. Their skin develops a bright orange color, a sign that they are reaching the peak of flavor. They will hold for up to three weeks before their quality begins to decline. To harvest, grab their tops just above ground level and pull. If they resist, moisten the soil to ease pulling.
Carrots store well and can be kept in a root cellar for up to six months if properly packed.
Seeds can be saved for up to three years under good storage conditions.