How to grow garlic in a greenhouse? When to plant and how to care for it?

Garlic – an unpretentious, but demanding to certain conditions crop, which can be successfully grown in a greenhouse to obtain a high yield all year round. However, for this it is necessary to properly prepare the soil, observe the temperature and humidity conditions, competently organize planting and care.

Optimal conditions for growing garlic in a greenhouse

Temperature and humidity

• Optimum germination temperature: +3…+5°C.
• Optimum growth temperature: +15…+20°C.
• Critical temperature: above +25°C can cause early yellowing of leaves and reduction in bulb size.
• Soil moisture: 70–75%.
• Air humidity: 50–60%.

Lighting

• Garlic requires at least 12 hours of light per day.
• In winter, supplementary lighting with LED phytolamps (6500K) is recommended.
• When growing in spring and autumn, natural light is sufficient.

Tip: It is advisable to use an automated ventilation system in the greenhouse to prevent overheating and excess humidity.

Choosing a Variety of Garlic for a Greenhouse

Type of garlic	The best varieties for a greenhouse	Peculiarities
Winter	"Lyubava", "Sofievsky", "Gulliver"	High yield, winter hardiness, strong taste.
Spring	"Victorio", "Gulliver", "Alenka"	Stores longer and forms dense heads.

Tip: To get garlic all year round, combine the cultivation of winter and spring varieties.

Preparing the soil in the greenhouse

1. Digging the soil to a depth of 25–30 cm.
2. Addition of organic matter – humus or compost 5 kg/m².
3. Optimize pH to 6.0–7.0; add ash or dolomite flour if necessary.
4. Mineral fertilizers:
   • Superphosphate – 30 g/m².
   • Potassium salt – 15 g/m².
   • Ammonium nitrate – 10 g/m².
5. Drainage – in heavy soils, it is recommended to add sand or perlite to improve water permeability.

Tip: Using mulch (straw, agrofibre) will help retain moisture and reduce the risk of weeds.

Technology of planting garlic in a greenhouse

Planting dates

• Winter garlic: October – November (for harvesting in May-June).
• Spring garlic: March – April (for harvesting in August-September).

Planting scheme

• Planting depth: 3–5 cm.
• The distance between the teeth is 8–10 cm.
• Row spacing: 20–25 cm.

Tip: It is better to plant garlic in cloudy weather or in the evening to avoid the soil drying out.

Caring for garlic in a greenhouse

Watering

• After planting: moderate watering to avoid rotting.
• During the period of active growth: once a week, 5–6 l per 1 m².
• 3 weeks before harvest: stop watering.

Tip: Avoid stagnant water - this is the main reason for garlic rotting.

Top dressing

1. Phase 3–4 leaves: nitrogen fertilizers (urea 10 g/10 l, mullein infusion 1:10).
2. Formation of bulbs: phosphorus-potassium fertilizers (superphosphate 15 g/10 l, ash 200 g/m²).
3. Before harvesting: stop fertilizing.

Tip: Alternate mineral and organic fertilizers for a balanced diet.

Protection from diseases and pests

Main diseases:

• Fusarium – soil treatment with Fitosporin solution.
• Bacterial rot - avoid overwatering, use drainage.
• Downy mildew – ventilation, treatment with copper sulfate.

Main pests:

• Onion fly - dust with ash, plant next to carrots.
• Thrips – treatment with infusion of garlic and laundry soap.
• Nematode – crop rotation, soil treatment with preparations based on nematicides.

Advice: Observe crop rotation – do not grow garlic in one place more than once every 3–4 years.

Harvesting and storing garlic

• Winter garlic is ready for harvesting in May-June.
• Spring garlic is harvested in August-September.
• Signs of maturity: yellowing and drying of the lower leaves.
• Storage: at +1…+3°C in a dry, ventilated room (up to 8 months).

Tip: To better preserve garlic, you can braid it and hang it up.

Growing garlic in a greenhouse

Growing garlic in a greenhouse allows you to get a stable harvest all year round, regardless of weather conditions. However, success depends on the correct choice of variety, soil preparation and compliance with the watering and fertilizing regime.

If you want to create ideal conditions for garlic and other crops, choose greenhouses from NovaTeplitsa. They reliably protect plants, create an optimal microclimate and help to obtain a high yield. Check out the greenhouse models on our website and ensure a rich garlic harvest!