In The Greenhouse This August

August in the greenhouse is a crucial month for managing heat, maintaining crops, and preparing for autumn. Here are your top tips for greenhouse care in August:

🌡️ 1. Ventilate, Ventilate, Ventilate 

• Keep vents and doors wide open during the hottest parts of the day to prevent overheating. 

• Use shade paint, shade cloth, or blinds to reduce sun intensity. 

• Avoid temperature spikes above 30°C (86°F) which stress plants. 

💧 2. Water Consistently and Deeply 

• Water early morning or late afternoon to reduce evaporation. 

• Check moisture daily—greenhouse soil dries out fast in August heat. 

• Use self-watering systems or drip irrigation if possible to keep watering steady. 

🍅 3. Support and Prune Crops 

• Tie up tomatoes, cucumbers, and beans to keep growth manageable and improve air circulation. 

• Remove lower leaves on tomatoes to reduce risk of blight. 

• Pinch out side shoots on tomatoes if necessary. 

🌿 4. Harvest Frequently 

• Pick tomatoes, cucumbers, peppers, and herbs regularly to encourage continued production. 

• Remove any diseased or damaged fruit and leaves promptly. 

🐛 5. Watch for Pests & Diseases 

• Aphids, whitefly, and red spider mites love greenhouse warmth. 

• Use insecticidal soap, neem oil, or introduce natural predators like ladybirds. 

• Inspect plants daily for early signs of disease or infestation. 

🌱 6. Sow and Plant for Autumn 

• Start sowing leafy greens (lettuce, spinach, mustard greens) for autumn harvest. 

• Sow overwintering crops like broad beans and garlic towards the end of August. 

• Consider planting hardy herbs like parsley and coriander for late season. 

🧴 7. Clean Up 

• Remove spent plants, old leaves, and fallen debris to reduce disease pressure. 

• Sterilise tools after use and consider wiping down greenhouse surfaces. 

🪴 8. Manage Nutrients 

• Feed fruiting crops weekly with a high-potash fertiliser.

• Watch out for signs of nutrient deficiency such as yellowing leaves. 

🌾 9. Prepare for Autumn Crops 

• Clear space as summer crops finish. 

• Plan your crop rotation to avoid soil-borne diseases next season. 

☀️ 10. Shade and Insulate 

• Use shade cloth during the hottest weeks to prevent scorching. 

• Towards the end of the month, think about insulating or sealing gaps to prepare for cooler weather ahead.