Container-grown carrots (Daucus carota) are a solution to a number of problems. For those living in areas with dense clay soils, containers may be the only way to get full-size carrots, because dense soils simply don't allow the root to form properly. For gardeners with limited mobility, or very little space to grow food, container carrots can be grown on patios with easy accessibility. Grow healthy, tasty carrots by selecting the right container, soil mix and location.
Varieties for Container Growing
When planting carrots in a container, look for short, thick varieties. These options take advantage of the loose soil in a container while not requiring the deep soil provided by in-ground gardens. Nantes is a specific variety of carrot that is thicker and shorter than many other types, but there are also other varieties of carrots well-suited for container growing. When browsing seed catalogs look for terms like "compact" and "good for containers."
- Baby Spike (_Daucus carota, 'Baby Spike')_ is a fast-maturing baby carrot that has a 3- to 4-inch root at maturity that stays tender.
- The Miami F1 carrot (Daucus carota, 'Miami') is a Nantes-type with uniform 6-inch roots with sweet flavor.
- For those who want a little more color to their carrots, Scarlet Nantes (Daucus carota, 'Scarlet Nantes') has bright orange 6-inch roots.
Containers for Growing Carrots
Select a container for carrots that will hold enough soil to be at least 2 inches deeper than the mature size of the carrot being grown. For example, if the carrot is a uniform 6-inch size, select a container that holds no less than 8 inches of soil and, because containers are filled to about 2 inches below the top, is no less than 10 inches tall. If the specific carrot description says 8 to 12 inches, then select a container depth based on the largest possible length for the variety. That is the minimum, but it doesn't hurt to go a little deeper -- it is better to have soil that is too deep than too shallow.
There is no requirement for the width of a container, select something that fits in the space and will hold the desired number of carrots when seedlings are thinned to 2 inches apart.
Plastic or terra cotta pots, grow bags or wood planters are all suitable options for growing carrots. Food-grade 5-gallon buckets or 55-gallon food-grade barrels are economical choices for containers. Make sure containers have at least one drainage hole large enough for excess water to drain out.
Never use a container that has stored chemicals or that is made of treated wood, as these can leech chemicals into the soil.
Mix equal parts compost and sand. Combine well and fill the container up to about 2 inches below the top of the container. This mixture creates the loose, well-drained soil required by carrots with moderate nutrients and neutral acidity.
Container Carrot Requirements
In USDA zones 7 and cooler, plant carrots three weeks before the last expected frost date in spring. In zones 8 and warmer, plant carrots in the fall or winter. Sprinkle seeds and cover with 1/4 inch of soil mix. Water well after planting and keep the soil consistently moist until seedlings have germinated and while they are young plants. Never let seedlings dry out completely. Thin seedlings to one carrot every 2 inches when they are 4 inches tall.
Keep the container in full sun. As carrots start to develop thick roots and grow to about 4 to 6 inches tall, only water when the soil is dry 1 inch below the surface.
For a continuous harvest of carrots throughout the growing season, use succession planting by planting a new set of seeds every two or three weeks.
Because the container mixture contains compost, this mix already has all the nutrients required by carrots. No further fertilization is required.