Hydrangeas are very popular plants in Portuguese gardens, but specialists warn that September may not be the best time to prune these flowers. The problem lies in the fact that some hydrangea varieties begin preparing flower buds for the following season well in advance. According to the Royal Horticultural Society (RHS) guide, cutting the wrong branches at this time can result in a plant full of leaves but with few flowers or even no flowers when the next flowering season arrives.
One of the main difficulties is that there are different types of hydrangeas that do not produce flowers on the same branches. Hydrangeas that bloom on old wood, such as many varieties of Hydrangea macrophylla, one of the best-known species, produce next year's flowers on branches that grew during the previous season. When late pruning is done, there is a risk of inadvertently eliminating those future flowering points.
The problem may go unnoticed because, after too-late pruning, the hydrangea continues to appear healthy, producing leaves and new growth. The consequence only becomes evident when the flowering season arrives again. However, not all hydrangeas follow this rule, since species such as Hydrangea paniculata and Hydrangea arborescens bloom on new wood, that is, on branches that grow during the current season itself.
The article recommends that, when it is not possible to identify the variety with certainty, it is preferable to avoid aggressive cuts during this phase. Besides pruning, experts also point out that it is important to pay attention to fertilization, avoiding nitrogen-rich fertilizers that may excessively stimulate the formation of new shoots, and not to abandon watering if September remains hot and dry. The most important thing is to observe the conditions of the soil and the plant itself rather than automatically following the calendar.
