Useful Tips for Growing Spanish Black Radishes in Pots

Spanish black radishes are known by the scientific name Raphanus sativus L. var. niger. They belong to the Cruciferae family along with other members such as Brussel sprouts, spinach, kale and cabbage. The health benefits that black radishes bring about have long been recognized by Chinese and European people who use the root to treat gall bladder and digestive issues. Indian also use the black radishes to address liver diseases. Spanish black radishes are generally considered to be helpful in treating gallstones and elevated cholesterol, promoting detoxification, protecting against bone marrow toxicity and improving intestinal health. Growing this type of radish in pots is not too difficult, therefore you may want give it a try by following our simple growing tips below and supplying yourself with fresh, healthful black radishes.

7 Useful Tips for Growing Spanish Black Radishes in Pots

1. Season considerations

Radishes develop well in the cool season, so the right time for growing them is spring and fall. However, if you plant them in pots indoors, the temperature can be easily adjusted to best fit black radishes’ growing temperatures. Common radishes take about 25 days to reach maturity while black radishes may take two to three times longer from planting till harvesting.

2. Seeds, pots and soil preparation


There are basically two types of black radishes, a round variety and a long cylindrical type that may reach up to 8 inches in length. Black radishes are commonly more peppery and spicy flavored than their rosy red counterparts. As soon as you’ve decided to grow your black radishes, look for different seed varieties from your local grocery or gardening stores and once you have purchased some you can prepare your pots accordingly. The long cylindrical type of radish will need deeper pots than the round variety. Black radishes will need at least 6 hours of sunlight daily, so be sure you place the pots in a well-lit area. In terms of soil, black radishes grow well in well-drained loamy soil at pH levels ranging from 5.8 to 6.8. Packaged potting soil with an adequate mixture of manure and nutrients will be best for growing them in. If you want to rather use garden soil, add some compost or manure to provide more nutrients for the growing radishes.

3. Sowing and spacing


Sow the seeds directly into the soil at ¼ to ½ inch deep and water well to keep them moist. Make sure the soil is loose, penetrable and free of stones. Once the plants are about ½ an inch tall, they can be thinned out to 2 inches apart from one another. The thinned out plants are a wonderful, fresh tasting, nutritious addition to salads or sandwiches,. You can also transplant the extra seedlings into other pots to continue growing at optimal spacing.

4. Care

Black radishes do not require a lot of care. The unfussy black radishes grow trouble-free as long as the soil is kept moist and well-drained. As mentioned previously, 6 hours of exposure to sunlight a day is crucial for their growth. As long as sufficient sunlight, water, nutrients, spacing and weed control are maintained, black radishes will grow healthily and be ready to be harvested after around 55 to 70 days from sowing.

5. Dealing with pests and diseases

Although most black radishes grow well with almost minimal care, there is a slight chance of pest invasion, so you need to keep an eye open for this and take action at the first signs. Flea beetles, slugs, cutworms, and aphids are among the more common attackers of black radishes. They eat the leaves and stems, and may damage the bulbs as well. As you grow Spanish black radishes in containers, plastic sheeting and wrapping around the base could be a preventative measure for these pest attacks.


If you notice that your radish leaves are turning yellowish, it could be a sign of disease or unhealthy growth. The causes of those diseases may be overcrowded, inadequate sun, weeds, fungal development or a virus infection carried by pests. The diseases could spread very quickly among the plants, so as soon as you notice any infected plants, remove them immediately. Controlling weeds is also a very good way to prevent diseases from gaining a foothold.

6. Harvesting


Black radishes are ready to be harvested when they are 3 to 4 inches across. If left too long in the ground after maturity, the bulbs get spongy and more peppery. The top portion of the radishes emerging up through the soil signifies that they should be picked. Pull up the whole plant by gently loosening the surrounding soil to pull up the radishes. The mature black radishes should be firm, smooth and covered with black skin.

7. Storing

Traditionally, root vegetables are stored in a cool place after washing such as the floor of a shed, but this conventional storage method may not help to keep the black radishes fresh for long. The fridge is the best place to keep the black radishes fresh after harvesting- you just need to remove the top leaves and keep the bulbs in plastic bags. If you just put the whole plant in the refrigerator, the leaves will soon lose their nutritional value during storage. They can actually be served separately from the bulbs if eaten within 2-3 days, while the bulbs can be kept for longer.


Spanish black radishes can be eaten raw in salads, boiled, steamed, or roasted. Peel the black skin off, then submerge them in salt water for two hours to lessen the spicy taste. No matter how you want to serve black radishes with your meal, the flavor should be special because you’ve taken the time to grow them yourself!

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