Rosemary does best in slightly dry soil, and should only be watered when top 1-2 inches of soil are dry. In the early stages after planting, rosemary needs regular watering to establish itself and become well rooted, but once it is established it requires very little water. Poor plant health and root rot are usually caused by excess water. In hot weather, container-grown rosemary may require more frequent watering than in-ground plants. Be sure to provide excess water that drains promptly for healthy root and vigorous growth.
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