What is the best strategy for controlling dandelions in late July?

Using a postemergence herbicide is the most effective strategy for controlling dandelions in late July because this timing coincides with the general growth cycle of dandelions. At this point in the season, dandelions are mature and have already established themselves as broadleaf weeds. Postemergence herbicides target these actively growing plants, allowing for effective absorption and action against the existing dandelion population.

In contrast, applying a preemergent herbicide would be ineffective at this time since preemergent herbicides are designed to prevent weed seeds from germinating, and by late July, dandelion seeds are likely already germinated and established. Watering the lawn frequently can promote overall grass health, but it does not directly control dandelions. Increasing mowing frequency can help manage the appearance of dandelions, but it does not eliminate the root of the problem, as it may allow the plants to persist and flower, leading to seed production. Thus, targeting dandelions with a postemergence herbicide provides the most direct control at this time of year.