Growing Radishes on an Allotment

Radishes are one of the fastest and easiest crops you can grow on an allotment. Many varieties are ready in as little as 3–5 weeks, making them perfect for beginners, succession sowing, and filling gaps between slower crops. The key to good radishes is cool conditions, consistent moisture, and regular harvesting.

This guide covers how to grow radishes from seed and plug plants, when to plant, spacing, watering and feeding, pests and diseases, container vs ground growing, and proven ways to improve yields.

🌱 1. Types of Radishes

🌸 Spring & Summer Radishes

• Small, round or oval roots

• Mild to peppery flavour

• Fast growing

🌿 Winter Radishes (Mooli / Daikon)

• Long roots

• Slower growing

• Milder flavour, larger size

(Growing methods are similar; spacing and timing differ.)

🌰 2. Ways to Grow Radishes

From Seed (Best & Most Common)

Pros

• Extremely easy

• Very fast results

• Cheap and reliable

Cons

• Needs regular sowing for continuous crops

Plug Plants

Less common but possible.

Pros

• Useful for very early sowings under cover

• More controlled spacing

Cons

• Extra cost

• Radishes dislike root disturbance

👉 Direct sowing is strongly recommended for best results.

🗓️ 3. When to Sow & Plant Radishes

Spring & Summer Radishes

• Sow outdoors: March–September

• Under cover: February–October

Winter Radishes

• Sow: July–August

• Harvest: Autumn–winter

Succession sow every 2–3 weeks for a steady supply.

🌾 4. How to Grow Radishes in the Ground

Soil & Position

• Light, free-draining soil

• Moist but not waterlogged

• Sunny or lightly shaded position

Avoid freshly manured soil — it causes leafy growth and poor roots.

Spacing

• Between plants: 2–5cm

• Between rows: 15cm

Crowding causes:

• misshapen roots

• slow growth

Sowing Depth

• Sow seeds 1–2cm deep

• Keep soil moist until germination (5–10 days)

🪴 5. Growing Radishes in Containers

Radishes are excellent container crops.

Container Guidelines

• Depth: 10–15cm minimum

• Window boxes, pots, troughs all work

• Use fine, stone-free compost

Containers dry out quickly — water regularly.

💧 6. Watering Radishes (Very Important)

Radishes need steady moisture.

Best Practice

• Water little and often

• Never allow soil to dry out

• Mulch lightly in warm weather

Dry stress causes:

• woody roots

• strong, bitter flavour

• splitting

🌿 7. Feeding Radishes

Radishes are light feeders.

Feeding Rules

• Compost before sowing is usually enough

• Avoid nitrogen-rich fertilisers

• No feeding needed for short crops

Overfeeding causes leafy tops and tiny roots.

🐛 8. Common Pests & Diseases

Flea Beetle

Symptoms

• Small holes in leaves

Control

• Keep soil moist

• Use fleece or fine mesh

• Sow little and often

Slugs & Snails

• Eat young seedlings

Protect early sowings.

Splitting Roots

• Caused by irregular watering

Maintain even moisture.

✂️ 9. Harvesting Radishes

When to Harvest

• Harvest as soon as roots reach size

• Don’t leave too long in the ground

Older radishes become:

• pithy

• bitter

• hollow

Check size regularly — growth is rapid.

🌾 10. Improving Radish Yields

• Sow little and often

• Keep soil moist

• Harvest promptly

• Grow in cooler conditions

• Thin seedlings early

Radishes reward attention, not feeding.

⚡ Quick Radish Growing Tips

• Fast crops = frequent sowing

• Moist soil keeps roots crisp

• Shade in hot weather

• Don’t overfeed

• Perfect gap-filler crop

🧠 Key Radish Principles

• Speed is everything

• Moisture controls flavour

• Harvest early and often

• Direct sowing works best

Photo by Markus Spiske on Unsplash