Organic soil is the preferred choice for household gardens growing small quantities of fruits and vegetables. Home-grown carrots are a steady source of nutrition throughout the year. They have a unique flavor that cannot be found in supermarkets. Using organic soil for growing carrots negates the use of harmful chemical fertilizers.
TIP: Because carrots do best in cooler weather, you can plant them in the fall and have an autumn harvest. Think back to the date of first frost last year. Pick a date three months before first frost, and sow your carrots like you would in the spring. In very hot southern climates, the summer heat can quickly ruin a carrot crop and early spring or fall plantings will increase your yield exponentially.
The usual varieties of home-grown carrots are suited for organic soil but have slightly different needs.
Planet Carrots - Also called thumbelina, these can grow well in heavy soil and are best suited for shallow soil depth. They grow well in containers, and mature much faster than other types. They look less like a grocery store carrot and more like a radish.
Chantenay - These carrots are cone shaped with a wide top and tapering point. They can withstand some clay in the soil.
Danvers - These are also conical and are very hearty. They are a common choice for silt-clay soil mixes.
Nantes - These carrots are very tender and stay roughly the same size from their top to tip. They will only grow well in good loose soil.
Imperators - These are very long and narrow, and will only grow in very deep sandy soil.
Organic Soil Basics
Ideally, carrots should be long, tapering, with a slender frame. For this, it is mandatory that your organic soil bed is well-drained. Soft, well-watered, and lightly sandy soil is a must for the carrot roots to grow deep. Organic soil is naturally loaded with many ingredients that make it perfect for growing carrots. However, it does need some basic management and the addition of certain materials. Carrots prefer soil in the pH range of 6.5 to 7.5, so make sure to test your garden soil before planting.
TIP: Before sowing your carrot seeds, use a rake or rototiller to dig the soil down 8 to 10 inches, turn it over, and mix it up. Remove any rocks and roots, and break up soil clumps. This is a good time to add the organic matter discussed below.
Soil Fertility — Organic soil is naturally fertile, having a high-density of naturally-occurring microorganisms and a high mineral content. If you are growing carrots in small containers, the potting soil needs to be enriched with compost. Most varieties of carrots need a slightly-acidic soil. This can be achieved by digging ½-inch compost into the upper soil layer, before planting.
Soil Texture — Most organic soils are suited for growing carrots, owing to their more maneuverable texture. However, some of them may have a high density of clay that can be difficult to work with. Soil beds with excess of clay soil can be improved by the addition of organic derivatives such as Humus. Conventional gardeners recommend using peat for making the garden soil nutrient-rich and softer, but humus soil is regarded as the best solution.
In fact, humus addition is regarded nearly 8 times more effective that organic manures and compost addition. Humus fertilizers are commonly available and they are recommended for ensuring that your carrot seedlings are able to sprout and root deep into the soil. Ideally, you should be mixing your garden soil with dried humus in a ratio of 2:1
Humus soil provides the ideal conditions for carrot growth as:
- It has a lower soil density
- The buffering capability of the soil bed is greater
- Micro flora of the soil multiplies at a rapid rate
- Strong granules help in water retention
- Sprouting density is increased by nearly 20 percent
Whatever your organic additive of choice, be it hummus, peat moss, coconut coir, or chopped fall leaves, mix it thoroughly into the top 6 to 8 inches of the soil to amend heavy clay.
TIP: Carrots much prefer sandy soil, though not many gardeners have naturally sandy soil on hand. For the best possible carrot shape, amend your soil with a few handfuls of builder's sand per every square foot.
Mulching — Carrots need a soil bed that remains constantly moisturized. However, constant watering could be a bit demanding. Mulching reduces the need for repeated watering by helping the soil retain moisture for a longer period. When the carrot seedlings are 3 inches tall, you should thin them apart by about 3 inches and then mulch them. Be thorough because crowded carrots produce crooked fruit. Exposed carrot shoulders have a tendency to become bitter and greener. This can be avoided by covering the shoulders with some organic mulch. Chopped fall leaves and straw both make great organic mulches.
Fertilizers — Carrots should be fertilized when their tops reach 3 inches in height. Choose a fertilizer that is lower in nitrogen (the first number) because nitrogen promotes foliage growth, not root growth. A 1-2-2 or 5-15-15 preparation will work just fine. Being a root crop, carrots can always use some additional potassium. Organic potash or potassium (K) is critical for the correct stomatic function and enzyme activity.
TIP: You can tell your carrots have a potassium deficiency when their foliage above ground is stunted and small.
Potassium directly affects the sweetness of the carrots. You should use any brand of organic potash with a 0-0-30 rating. For adding potash, use the simple calculation of 2 pounds of it for every 100 square foot of your soil spread.
TIP: Keep in mind that potash raises the pH of soil and should not be used in alkaline soil. Kelp is another amazing organic fertilizer that can be added to the soil before planting, along with compost or manure.
Removing Pests — the carrot fly is a typical problem for any garden that grows carrots. You can detect this problem if you see rusty brown scars on the fruit. When you cut into the root, you will see tunnels and maybe even creamy yellow larvae. One simple way to get rid of them is immediately discarding the carrot thinnings when you harvest the garden. Carrot flies are attracted to crops by smelling the carrot thinnings laying on the ground. However, the most effective method is to use companion planting. Carrot flies are deterred from invading gardens that have tomatoes grown in combination with carrots. Companion gardening is a highly-effective organic gardening technique. Carrot fly resistant cultivators are also available on the market.
TIP: Every couple of weeks up until early August sow some more carrot seeds in different parts of the garden This staggering ensures that you have a steady supply of fresh carrots throughout the season.