Growing carrots indoors is an easy solution to having little or no space for an outdoor garden. Three varieties of carrots include short-root, medium-root and long-root. For the purpose of container gardening, short-root carrots are best. Due to their shorter root system, they don't require as much space, making them ideal for planting in containers.
Containers should be at least two gallons, in order to allow for root development. A two-gallon pot measures around 10 inches across the top.
Containers may be clay or plastic. Carrots planted in clay containers may need to be watered more often than carrots planted in plastic containers. Clay containers draw moisture away from the carrots' roots, causing the soil to dry out faster. Plastic containers will hold moisture longer.
Carrots grown indoors require a lightweight soil mix. Basic garden soil is not suitable for growing carrots in containers due to its clay content.
Garden centers have a wide variety of potting mixes for container vegetable gardens. They also carry soilless mixes, which are ideal for container vegetables. Soilless mixes are packed with nutrients and have good drainage quality. Nutrients help carrots thrive, and good drainage quality will hold the correct amount of water for the carrots' root system to develop.
Carrots grown indoors in containers need at least six hours of sunlight per day. Containers of carrots placed near sunny windows or in a sun room should offer a sufficient enough amount of sunlight. Using a soilless potting mix helps keep containers light enough to move around if needed.
Container carrots should be watered so that six inches of soil depth is wet. Watering cans, indoor water hoses and self-watering accessories are available for growing carrots indoors. Containers used for carrot gardening should have drainage holes in the bottom. Many containers come with drainage holes, but some do not.
Carrots grown in containers need additional fertilizer as opposed to carrots grown in the ground. A water-soluble fertilizer designed for container vegetables is best, and should be applied at least every two weeks. Garden centers carry many types of fertilizers in both powder or liquid form. Note that even if using a soil high in nutrients, fertilization is still recommended.