Carrots go in the third part of our rotation, after the leafy crops and fruits have lowered nitrogen levels, and our applications of phosphorus-and potassium-containing rock powders have enriched the beds. The bed is also relatively free of weeds after two years of clean cultivation, so we can be sure that the carrots will have a good chance to outrun any returning weeds. Carrots grown in nitrogen-rich soils can get quite large, but they’ll taste awful, and the roots will likely be hairy and misshapened.
In cool areas you can sow carrots throughout the growing season in temporal succession, planting a new crop every two to three weeks. In areas with hot summers, it’s best to limit yourself to spring and fall crops, as carrots grown and harvested in midsummer are likely to have a bitter, resinous taste.
Carrots do not transplant well. Sow the seed 1/4 inch deep in rows six inches apart. If you want a path between each row, add another foot. But carrots are one of the best crops for raised beds, because the freedom from compaction that a permanent bed gives them really helps their growth. Our three-foot-wide growing beds allow five rows per bed, running lengthwise. You can just as easily run the rows across the bed, which will make it easy to sow only as many feet of row as you’ll want to harvest and eat each week.
Sow the seed as thinly as you can. I learned from my grandfather to mix in a small amount of radish seed with the carrot seed, and sow them together. That not only makes sowing the small carrot seeds easier, but the quick-germinating radishes break up the soil surface when they emerge, which is a real help for the slow-sprouting carrots. It also makes it possible for me to cultivate the rows even before the carrots are up, and that means less weed pressure. Carrots do not compete well against weeds; by getting in early with the hoe you can make a big difference in the amount of weeding you’ll have to do later.
Harvesting the radishes a few weeks later also helps thin the carrots, normally one of the least satisfying garden jobs. By using this radish interplant I am able not only to get a “free” crop of radishes, but also to completely avoid thinning my carrots until they are the size of a pencil, and thus fit for the table. Then I can at least get something for the time I put in: sweet, tender baby carrots to snack on!
Carrots Love Radishes[youtube=http://www.youtube.com/watch?v=kj-kVaPBsgI&rel=0]
Carrots are not bothered by many pests and diseases. We occasionally have problems with the carrot rust fly on early crops (planted before May 15, two weeks before the last frost), but it’s easily controlled by putting down a floating row cover immediately after sowing. Leave the cover on until the radishes are ready to harvest, then harvest, weed, and thin all at once. We also get occasional visits from the Parsleyworm, which is the beautiful larval form of the Black Swallowtail butterfly. From there on care is a snap: just an occasional hoeing until the carrots close over their tightly spaced rows. Sometimes we’ll see a brightly colored parsley worm, but that is an easy pest to hand-pick and crush underfoot.
Like many other crops, carrots will sometimes split if the weather goes from a prolonged dry period into a wet spell. Regular watering during drought will prevent this. It is more of a problem with spring and summer carrots, as the fall varieties are more fibrous and less succulent, and so less affected by variations in the water supply.