How to grow radishes in a greenhouse? When to plant and how to care for them?

Radish is one of the earliest vegetable crops that can be grown in a greenhouse almost all year round. To get strong, juicy root crops without voids, it is important to choose the right variety, prepare the soil and follow basic agricultural practices. In this article, we will analyze all the stages of growing radishes in greenhouse conditions, from planting to harvesting.

Choosing a variety of radish for a greenhouse

Early maturing and low-light resistant varieties are suitable for greenhouse cultivation. They quickly form root crops and produce a stable harvest.

Optimal varieties of radish:

• Early ripening (18-25 days before ripening): “18 days”, “French breakfast”, “Saksa” – form small root crops with a delicate texture.
• Mid-season (30-35 days): “Duro”, “Rubin”, “Alba” – produce larger fruits, resistant to cracking.
• Late-ripening (40-45 days): “Red Giant”, “Ice Icicle” – suitable for long-term storage, have high resistance to diseases.

How to choose the best variety for a greenhouse?

• Low Light Tolerance: For winter and early spring growing, it is important to choose varieties that grow well in low light.
• Tolerance to temperature changes: hybrid varieties tolerate nighttime temperature drops better.
• Size and shape of root crops: in the limited space of a greenhouse, it is better to grow compact varieties with short root crops.
• Root depth: Some varieties develop closer to the surface, which can be useful for greenhouses with limited topsoil depth.

Expert advice: Mixed planting of varieties with different ripening times will allow you to harvest radishes continuously throughout the season, providing fresh root vegetables without the need to harvest large quantities at once.

Preparing the soil in the greenhouse

Radishes prefer loose, well-drained soil with neutral acidity (pH 6.0-7.0). Dense and clayey soils are not suitable, as they can cause the roots to bend and crack.

The main stages of soil preparation:

1. Deep digging – loosening the soil to a depth of 25-30 cm, removing stones and weed roots.
2. Enrichment with organic matter – adding humus (4-5 kg per 1 m²) or well-rotted compost to improve the structure.
3. Mineral fertilizers – application of superphosphate (20 g/m²), potassium sulfate (15 g/m²) and wood ash to saturate the soil with potassium.
4. Disinfection – pouring hot water or a solution of “Fitosporin” over the soil to reduce the risk of fungal infections.
5. Loosening the top layer – adding sand or vermiculite for better soil aeration.

Expert advice: For accelerated growth of root crops, it is important to maintain stable soil moisture at a level of 70-80%. Watering should be uniform, since sharp fluctuations in humidity lead to cracking of fruits.

When to plant radishes in a greenhouse?

Radishes can be sown in a greenhouse at almost any time of the year, depending on temperature conditions.

• Heated greenhouse – sowing is possible from February to November, maintaining a temperature of +15…+18°C.
• Unheated greenhouse – radishes can be sown from mid-March to October.
• Winter sowing is carried out in November-December, and the seeds are protected with covering material or mulch.

Optimal sowing conditions:

• Seed planting depth: 1-1.5 cm.
• Distance between rows: 10-15 cm.
• Optimal planting pattern: 4-5 cm between plants for good air circulation.

Expert advice: To improve germination, before sowing, seeds can be treated with growth stimulants (“Epin”, “Zircon”) and soaked in warm water for 6-8 hours.

Watering and microclimate in the greenhouse

Radishes require regular watering and stable growing conditions.

• Temperature conditions:
  • Before emergence: +16…+20°C.
  • After emergence: +12…+16°C.
  • Avoid overheating above +22°C – this leads to bolting.
• Watering:
  • Before seedlings appear, spray the soil daily.
  • After germination – water 2-3 times a week, 7-10 liters of water per 1 m².
  • A week before harvesting, watering is reduced to prevent the radishes from cracking.
• Air humidity: 60-70%.

Expert advice: On hot days, radishes can be shaded with agrofibre to avoid overheating, and in winter, when there is low light, LED phytolamps can be used.

Growing radishes in a greenhouse

Growing radishes in a greenhouse is an affordable and effective way to get a fresh harvest at any time of the year. The main thing is to choose the right variety, maintain the temperature regime and ensure stable humidity.

If you want to create ideal conditions for growing radishes, choose greenhouses from NovaTeplitsa. They provide reliable plant protection and create an optimal microclimate. Check out the models on our website and grow radishes with maximum efficiency today!