So I googled and here is some info you may like to look at.

http://www.amishlandseeds.com/garden_tips.htm

Transplanting Carrots and Garbage Planters
http://www.urbanhayseed.com/20.....-planters/

I just downloaded this little ebook I found while looking for an answer to your question on the internet. It is free to share. Maybe you will like it
http://www.freeplants.com/signup.htm

Planting Vegetables from Seed and Seedling
http://www.dummies.com/how-to/.....dling.html

Cheers
Mandy

To avoid these problems, take pains to prepare the seedbed for carrots well before sowing seed. Wait until the soil has dried out before digging it. Dig it up thoroughly, turning it over and breaking up lumps into small pieces. Cover the newly sown seeds with sand or fine soil that will not crust over when dry. Keep the soil moist. Provide shade for seeds planted in mid-summer so that the soil does not heat up. Garden fleece will do this job.
Top of Root Turns Green Because of too Much Sun
Sometimes carrots develop green “shoulders.” When the upper part of the developing root pushes above the soil line and is exposed to the sun, the tissues turn green. Vigorous growth or heavy rains that wash away soil usually cause this problem, but covering the carrot shoulders, but not the crown where the foliage emerges, relieves it. As carrot foliage grows thicker, it will shade the shoulders too. Cut off any green tops of harvested carrots and eat the orange part. The green part tastes bitter, but it’s not poisonous.
Roots Twist Around Each Other Because Of Crowding
Carrots that are twisted around each other are victims of overcrowding. It is essential to thin them out well, so that each carrot has about 2 inches of space to grow. Deformed carrots are still tasty and will store well; they just don’t look very much like normal carrots.
Carrot Roots Are Split, Hairy Or Tough Because Of Moisture Problems
Carrots are very sensitive to soil moisture levels. When the soil isn’t moist enough, the main root develops many small feeder roots so it can soak up any available moisture more efficiently. At the same time, it forms extra tissue to carry the water, so it becomes tough. On the other hand, if there’s too much soil moisture, carrots sometimes split along their whole length. This happens more often when they are close to maturity.
The key to assuring even, sufficient moisture to carrots and other plants is soil that’s rich in organic matter, which enables it to hold moisture, yet drain well. Improve your soil by adding chopped leaves, peat moss or compost, if you can get some. Try to keep the soil evenly moist during periods of irregular rainfall by watering regularly and deeply so that the soil does not dry out. Use mulch to prevent evaporation and run-off of moisture from the soil.
Carrots Are Covered With Hairy Roots Because Of Too Much Fertilizer
If harvested carrots are covered with small hairy roots, they may have had too rich a diet. To avoid overfertilization at any stage of their growth mix a slow-acting granular fertilizer into the soil in the spring when you plant. Do not feed the carrots for the rest of the season.

http://yardener.com/YardenersP.....sofCarrots