While most vegetables are suitable for planting in containers, some large vegetables with extensive root systems require containers that take up valuable space on a patio or balcony. Radishes are ideally suited for container growing, as the flavorful, fast-growing vegetables thrive in relatively small containers. Plant seeds as early as February, as radishes are cool season vegetables. Take a break during the heat of summer, and then plant another crop of radishes when temperatures drop in autumn.
Prepare a container at least 4 to 6 inches deep. A pot with a diameter of 16 inches accommodates approximately five radishes, while a 24-inch pot is large enough for 18 radishes. Ensure the container has a drainage hole in the bottom.
Fill the container with standard commercial potting mixture, as potting mixture is lightweight and drains well. Avoid regular garden soil, which becomes compacted and doesn't allow water to drain.
Incorporate a time-release fertilizer into the potting mixture. Use a complete garden fertilizer with a ratio such as 10-10-10 or 14-14-14. Apply the fertilizer at a rate of approximately 1/2 tablespoon of dry fertilizer for each gallon of potting mixture.
Sprinkle radish seeds on the surface of the soil. Cover the seeds with 1/4 to 1/2 inch of soil.
Water the radishes carefully to avoid washing the seeds from the soil. Add water until it trickles through the drainage hole. Thereafter, water whenever the top of the soil feels dry to the touch. Radishes may require irrigation every day during warm weather, as containerized soil dries rapidly.
Place the container where the radishes are exposed to at least six hours of sunlight per day.
Fertilize the plants when the radishes begin to emerge. Apply a balanced, water soluble fertilizer according to label specifications. Repeat every one to two weeks until harvest.
Thin the radishes when the plants reach a height of 1 to 2 inches. Allow 1 to 2 inches between each plant.
Harvest radishes as soon as they reach edible size -- no more than 1 inch in diameter. Don't wait, because radishes quickly develop a bitter flavor and woody texture.
Things You Will Need
- Container with drainage hole
- Commercial potting mixture
- Balanced, time-release fertilizer
- Hose or watering can
- Balanced, water soluble fertilizer
- University of Maryland College of Agriculture and Natural Resources: Planting and Caring for Your Container Vegetables
- San Francisco Seed Library: Planting Calendar for San Francisco
- The Ohio State University Extension: Container Vegetable Gardening
- Kansas State University Extension: Growing Vegetables in Pots
- University of Illinois Extension: Radish
- Iowa State University Extension: Container Vegetable Gardening
- Jupiterimages/Comstock/Getty Images