Like some other popular fruits and vegetables, radishes offer a substantial dose of vitamin C. Much research has been done on vitamin C’s effects on the immune system, but whether it plays a significant role is disputed. Vitamin C is an effective antioxidant molecule that works in the water-soluble portions of the body to disarm free radicals. Vitamin C helps reduce oxidative stress on blood vessels in the cardiovascular system (leading to plaque buildup) and lung cells. The anti-oxidants also deter free radicals from damaging plasma membranes and DNA, which may help prevent cancer-causing mutations. Vitamin C also works with an antioxidant compound, glutathione peroxidase, to help restore the activity of vitamin E (a fat-soluble vitamin). Vitamin C is an important part of collagen formation involved with healthy bone, skin and connective tissues. Radishes have phytonutrients that help aid digestion (by encouraging bile flow) and stimulate the liver to produce detoxifying enzymes that remove harmful chemicals in the blood. Radishes, both red and daikon, have the phytonutrient myrosinase, which acts as an enzyme to break down other phytonutrients in radishes (glucosinolates) to isothiocyanates. Ongoing research with isothiocyanates suggest these compounds may have strong anti-cancer properties.
Vitamin and Mineral Content
Vitamins – C, B9 (Folate), B6 (Pyridoxine) and B2 (Riboflavin)
Minerals – Potassium and Manganese
Regular eating of radishes may help reduce the symptoms or development of atherosclerosis, cardiovascular disease, cataracts, kidney stones and many types of cancers.
How to Grow
Radishes are a fast-maturing root to grow between slower-maturing vegetables. Highly tolerant of soil types but need cool weather to grow correctly. Like most veggies, radishes grow quickest in soil that has been worked with organic matter like aged compost or planting mix. Loosen up the soil to a depth of at least 1 foot to allow unhindered growth. Plant at the start of spring. Sow the seeds in rows 6 inches apart. Place seeds close together, roughly 1 inch apart. Thinning usually is not an issue. For a continual harvest, sow seeds weekly until weather begins to warm. You can begin sowing in mid- to late summer as the weather begins to cool for a fall harvest. Radishes are low maintenance. Most important is to water when the soil starts to dry and keep the area weed free. Mulching helps retain water and deter weeds. Harvest as soon as roots are mature. If they sit too long, they crack and get tough. Discard any that look diseased or damaged so they do not pass it on to other roots.
Cabbage maggots, flea beetles and carrot fly may affect root growth. If you suspect cabbage maggots, deter them by making floating row covers or make slits in a piece of foam carpet pad or tar paper, securing it around the base of each plant. This prevents maggots from burrowing down to the roots. You know you have flea beetles if they jump in the air like fleas as you bring your hand a few inches over them. To control, take a piece of cardboard or wood and coat one side with a sticky substance. Hover the board a few inches over the radishes and watch the beetles jump up and get stuck. The female carrot fly lays her eggs at the base of root plants. The larvae burrow into the roots. To prevent it, surround the bed with plastic screen.
Radish greens have up to 6 times the vitamin C of radishes themselves. Daikons are an Asian white radish grown the same way as red radishes with similar nutrient content and health benefits. Try both to see which you prefer.