Lawn by Season

When to Plant Radishes in New Brunswick

Published: April 24, 2026 · Updated: April 27, 2026

Fresh red radishes pulled from a garden bed
Canadian Zone 5bLast frost: May 10 – May 10

The fastest crop in the garden — ready in 22–30 days. Direct sow 4–6 weeks before last frost and succession plant every 2 weeks for a continuous spring harvest.

Radishes grow well in this province with appropriate variety selection and standard Canadian planting timing.

Radishes Planting Window for New Brunswick

Direct sow outdoors: April 5–15

Minimum soil temperature: 4°C (40°F)

Days to harvest: 2230 days

Sun requirement: Full sun to partial shade

Fall crop planting: September 7–17

Direct sow radishes 4–6 weeks before last frost — one of the fastest crops in the garden. Ready in as little as 22 days. Succession plant every 2 weeks for continuous harvest.

New Brunswick Cities — Radishes Planting Dates

City-specific frost dates and radish planting windows for New Brunswick.

Growing Radishes in New Brunswick

  • Thin to 2-inch spacing when seedlings are an inch tall — crowded radishes produce small woody roots.
  • Succession plant every 10–14 days from early spring through late spring for continuous harvest.
  • Plant as a row marker for slow-germinating crops like carrots — radishes sprout in days and mark the rows.
  • Harvest promptly at target size; over-mature radishes turn pithy, woody, and unpleasantly hot.

Companion Planting for Radishes

In New Brunswick gardens, pair radish with Lettuce, Carrot, Pea, Cucumber. Avoid planting near Hyssop, Grape, which compete with or inhibit radish growth.

Common Pests and Problems

Radishes in New Brunswick are commonly affected by Flea Beetle, Cabbage Root Maggot, Aphid. Floating row covers installed at planting block most adult pests from laying eggs, and a weekly scouting routine catches infestations before they damage the crop.

Frequently Asked Questions

When should I plant radish in New Brunswick?

In New Brunswick (Canadian Zone 5b), direct sow radish around April 5. Radishes grow well in this province with appropriate variety selection and standard Canadian planting timing.

What is the best radish variety for New Brunswick?

New Brunswick gardeners should prioritise varieties bred for shorter seasons or Canadian climates. For radishes in Canadian Zone 5b, look for cultivars labelled under 30 days to maturity. Local nurseries and provincial seed exchanges curate varieties that ripen within Canadian frost-free windows.

How does New Brunswick's climate affect radish?

New Brunswick spans Canadian Zone 5b with frost-free seasons ranging from roughly 151 to 155 days. Radishes actually prefer the cooler spring and fall windows typical of New Brunswick, making them one of the most reliable crops in the province.

Can I grow radish in containers in New Brunswick?

Yes. Container growing on balconies and patios extends the viable growing area across every Canadian province. Dark-coloured containers warm up faster in spring and extend the season on both ends. Choose a 5-gallon or larger pot for radish and water daily during hot summer weather, since containers dry out quickly.

When is the first fall frost in New Brunswick?

First fall frost dates in New Brunswick range from October 8 in the coldest areas to October 12 in the warmest. For a fall radish crop, count back from your local first-frost date and plant around September 7–17.

Related Guides

Get alerted when restrictions change

Free email alerts for your city – know before you water.

No spam, ever. Unsubscribe anytime.