In The Greenhouse This June

Here are the top greenhouse gardening tips for June, when warmth and light are at their peak — and so are the demands of your plants: 

 🌡️ 1. Ventilate Daily 

• Open vents and doors during the day to prevent overheating. 

• Use automatic vent openers or shade cloth to regulate temperature (aim for 20–25°C). 

• Avoid still, humid air — it encourages pests and disease. 

🌞 2. Provide Shade 

• Use shade netting, greenhouse paint, or blinds to protect plants from scorching midday sun. 

• Essential for salads, seedlings, and young plants.

💧 3. Water Regularly and Consistently 

• Check daily; water in the morning to avoid fungal issues. 

• Use watering cans, capillary mats, or drip systems for even moisture. 

• Don’t let compost dry out in pots or grow bags — it’s easy to miss. 

🪴 4. Feed Hungry Crops 

• Start feeding tomatoes, peppers, cucumbers, and aubergines weekly with a high-potash liquid fertiliser (like tomato feed) once flowering begins. 

🌱 5. Sow Summer and Autumn Crops 

     Ideal for sowing: 

• Lettuce, rocket, radish, spring onions

• French beans (for containers or late crops)

• Florence fennel, pak choi, and other quick-growing crops

• Start biennials like wallflowers and foxgloves if you use greenhouse space for ornamentals. 

🪰 6. Watch for Pests and Diseases 

     Check regularly for: 

• Aphids, red spider mites, whitefly, and mealybugs

• Fungal diseases like grey mould (botrytis) 

• Use sticky traps, natural predators (like Encarsia for whitefly), or organic sprays if needed. 

🌿 7. Train and Support Vining Crops 

• Tie in tomatoes, cucumbers, and melons to supports. 

• Pinch out side shoots on cordon tomatoes and remove lower leaves to improve airflow. 

♻️ 8. Keep It Clean 

• Sweep up debris, remove dead leaves, and disinfect surfaces regularly to reduce disease risk. 

• Clean tools and pots after use. 

🍅 9. Pollinate by Hand (If Needed) 

• In still air, help fruiting by gently shaking tomato plants or using a soft brush to transfer pollen between flowers. 

🔄 10. Rotate and Reuse Wisely 

• Avoid growing the same crop in the same grow bag or container soil year after year. 

• Reuse compost by topping up with fresh and using it for leafy greens or flowers — not fruiting crops.