Yard and Garden: Radishes

April 11, 2013, 7:24 am | Richard Jauron, Willy Klein

AMES, Iowa — Radish is a cool-season, fast-maturing, easy-to-grow vegetable. Garden radishes can be grown wherever there is sun and moist, fertile soil, even on the smallest city lot. 

What are some good radish varieties for the home garden? 

RadishesSuggested radish varieties (cultivars) for home gardens include:

  • ‘Champion’ – scarlet red, globe-shaped, white flesh, 20 to 25 days
  • ‘Cherriette’ – cherry red, globe-shaped, white flesh, 20 days
  • ‘Cherry Belle’ – bright cherry red, round to globe-shaped, white flesh, 24 days
  • ‘Easter Egg II’ – blend of red, purple, and white radishes, round, 28 days
  • ‘Ping Pong’ – pure white, round, white flesh, 30 days
  • ‘Red Satin’ – bright red, round, white flesh, 23 days
  • ‘Sparkler’ – bright red top with white tip, round, white flesh, 25 days
  • ‘White Icicle’ – snow white, slender tapered 4 to 6 inches long, white flesh, 28 to 30 days

When can radishes be planted in Iowa? 

Radishes can be planted as soon as the ground can be worked properly in spring. This is often late March in southern Iowa and mid-April in northern counties. Successive plantings can be made every 7 to 10 days through May. Radish plants flower and their roots become pungent with the onset of hot weather. Several plantings can also be made in late summer (late August to late September) for a fall crop.

Sow radish seeds ½ inch deep in rows that are 12 inches apart. When the seedlings emerge, thin the planting so remaining plants are 2 inches apart.

When should radishes be harvested? 

Radishes can be harvested three to five weeks after planting. Periodically check their development by pulling one or two plants as they approach maturity. Harvest radishes when roots reach useable size (about 1 inch in diameter). Radishes can be stored in the refrigerator for two to three weeks. Prior to storage, cut off the foliage to within ½ inch of the roots. Radishes get pithy and hot when harvested too late.

My radishes produce lush foliage, but don’t develop good-sized roots. Why? 

Excessive nitrogen, the rapid onset of hot weather or overcrowding may produce plants that are all tops (lush foliage, little or no root development).

Misshapen roots and hot, pithy radishes are other problems that may be encountered when growing radishes. Overcrowding produces small, misshapen roots. Hot, pithy radishes may be result of hot weather or harvesting too late. 


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