Alan Titchmarsh has advised gardeners to plant French marigolds alongside tomatoes to deter whiteflies, a common pest that can devastate tomato crops. In a video on his YouTube channel, the horticultural expert explained that the strong scent of marigold roots helps repel whiteflies when grown in the same soil or container.
Whiteflies pose a significant threat to tomato plants by draining sap from leaves and stems, causing yellowing, curling, and eventual leaf drop. Titchmarsh noted that companion planting with French marigolds offers a natural alternative to chemical sprays, as the root exudates of the marigolds mingle with those of the tomato and deter the pests.
French marigolds also attract pollinators with their nectar and pollen, and add vibrant colour to gardens throughout summer. Titchmarsh emphasised that this method makes efficient use of space, as both plants can be grown together in the same grow bag, pot, or soil.
Companion planting is a technique where different plants are cultivated together for mutual benefit, enhancing plant health and yields while minimising pest issues. Titchmarsh cautioned that tomatoes should not be planted near potatoes, brassicas, or sweetcorn, but marigolds are an excellent companion.
