How to grow radishes

Frost-hardy · Cabbage family

When to sow and plant

Sow outdoors 29 March – 5 April

Based on: average for Germany, last frost 19 April, safe from 6 May

Where the dates come from

The weeks come from our sources; the dates use the average frost in Germany. Enter a German postcode to get dates for your area.

Sow outdoors: 2–3 weeks before the last frost (USU Extension: How to Grow Radishes in Your Garden)

Good and bad neighbours

Good neighbours · 3

SweetcornExpert rule· C
Radishes are harvested between the corn before it shades them out.
C: Expert rule with a reason
Sweetcorn
Brussels sproutsExpert rule· C
Radishes are harvested between the sprouts before these shade them out.
C: Expert rule with a reason
Brussels sprouts
PeaExpert rule· C
There is room for a row of radishes between two rows of peas.
C: Expert rule with a reason
Pea

Disputed · 1

CucumberDisputed· X
BUND lists radishes as bad cucumber neighbours; the Rhineland-Palatinate garden academy plants them next to cucumbers.
X: Sources disagree
Cucumber

Gardeners’ lore, not proven · 3

White cabbage, Red cabbage, Savoy cabbage, Cauliflower, Broccoli, Kale, Kohlrabi, Chinese cabbage, Pak choiLore: good· D
Considered a good pair; radishes are said to lure flea beetles away from cabbage. Not proven. Both are brassicas (clubroot).
D: Tradition, named by at least two sources
White cabbage Red cabbage Savoy cabbage Cauliflower Broccoli Kale Kohlrabi Chinese cabbage Pak choi
Swiss chardLore: good· D
Traditional advice, not tested.
D: Tradition, named by at least two sources
Swiss chard
TomatoLore: good· D
Traditional advice, not tested.
D: Tradition, named by at least two sources
Tomato

Crop rotation

After the cabbage family, leave the bed free of it for at least 4 years (sources: 4–5 years).

The same species should go back to the same spot after a break of 3 years at the earliest.
Example: grown here in 2026, again from 2031.
If clubroot has appeared in the bed: no plants of the cabbage family for at least 7 years, not even mustard as green manure.

At a glance

Family: Cabbage family (Brassicaceae)
Nutrient needs: Light feeder
Frost: Hardy, tolerates frost
Spacing (row × plant): 15 × 4 cm (6 × 2 in)
Plants per m²: 166.7
Per square foot (30 × 30 cm): 16 plants
Life cycle: Annual
Harvest: After 30 days from sowing

Spacing according to Bayerische Gartenakademie (LWG): Sä- und Pflanztermine auf einen Blick (2018). Other sources: 28 × 4 cm (11 × 2 in) (USU Extension: How to Grow Radishes in Your Garden); 6 × 6 cm (2 × 2 in) (Colorado State University Extension, GardenNotes #720: Vegetable Planting Guide).

Questions and answers

When can I sow radishes?

Sow outdoors, average for Germany: 29 March – 5 April. Enter a German postcode above for your area, or your own frost date in the planting calendar.

How far apart should I plant radishes?

15 × 4 cm (6 × 2 in) (row × plant), according to Bayerische Gartenakademie (LWG): Sä- und Pflanztermine auf einen Blick (2018).

What grows well next to radishes?

Sweetcorn: Good neighbour (C), Brussels sprouts: Good neighbour (C), Pea: Good neighbour (C), Cucumber: Disputed (X) and White cabbage, Red cabbage, Savoy cabbage, Cauliflower, Broccoli, Kale, Kohlrabi, Chinese cabbage, Pak choi: Gardeners’ lore, not proven (D).

How long a break do radishes need in the same bed?

After the cabbage family, leave the bed free of it for at least 4 years (sources: 4–5 years). The same species should go back to the same spot after a break of 3 years at the earliest.

Sources

Show 14 sources

Retrieved on 23 October 2026. Facts in our own words, one source per value.