Grows best in cool (50 F to 65 F), moist weather. Hot weather reduces
quality and increases pungency. Late plantings may bolt before edible
root forms.About
3 to 6 weeks before average last frost, direct seed ½ inch deep, 1 inch
apart, in rows 12 inches apart. Thin to about 2-inch spacings. Crowded
plants may not produce high-quality roots. Use thinings in salads.
For
continuous harvest, make additional plantings every 1 to 2 weeks until
temperatures average in the mid 60s F, or plant varieties with
different maturity dates in a single planting. Resume planting when
weather cools in fall.
Plant most winter varieties so that they
mature around the first fall frost date. (Frost improves flavor and
texture of most winter varieties.) Larger winter varieties need more
space than spring varieties, so thin to about 6-inch spacings,
depending on variety.
Keep soil moist for uninterrupted growth and best quality.
Adding nitrogen fertilizer or nitrogen rich manure close to planting may produce lush tops and small roots.
Can
be sown in the same row with carrots, parsley, parsnips and other slow
germinating crops. The radishes help to break soil crust for the weaker
and later-germinating crops.
Because they mature quickly,
radishes make a good intercrop along with slower growing crops, such as
other cabbage family crops, or tomato- or squash family crops. Or
follow radish harvest with summer succession crops such as beans, or
fall-harvested crops.
To help reduce disease, do not plant radishes or other cole crops in the same location more than once every three or four years.