Growing Basil in a pot

Basil needs consistent moisture throughout the growing season but is highly susceptible to root rot, so strike a careful balance. Water when the top 2–3 cm of soil feels dry, typically every two to three days in warm weather, less frequently in cooler or rainy spells. Water at the base of plants in the morning, keeping foliage dry to reduce the risk of fungal diseases such as downy mildew and fusarium wilt. In containers, check daily as pots dry out quickly. Feed every two to three weeks during June and July with a balanced liquid fertiliser diluted to half strength, or apply a slow-release granular feed at planting time. Avoid high-nitrogen feeds, which promote soft, disease-prone growth at the expense of flavour. Stop feeding by early August as growth naturally slows. Basil is not hardy in temperate Europe—it's rated for zones 10a–11b and will die at the first frost. Treat it as a summer annual and plan to sow or buy fresh plants each year. If you want to extend the season, pot up a plant in late August and bring it indoors to a sunny windowsill, though growth will be slower and flavour less intense than outdoor plants. Slugs and snails can devastate young plants; protect with barriers or organic pellets. Aphids occasionally cluster on shoot tips—rinse off with water or squash by hand. Downy mildew, recognisable by yellowing leaves with grey fuzz underneath, is the most serious problem, especially in humid conditions. Improve air circulation, avoid overhead watering, and remove affected leaves immediately. In wet summers, consider growing basil in pots under cover.