Autumn marks a crucial time for caring for Hydrangeas, those beloved flowering shrubs known for their stunning blooms. To ensure vibrant and plentiful blossoms in the upcoming summer, it’s vital to embrace proper hydrangea care during this transitional season. There are various types of hydrangeas, each requiring specific attention. However, certain fundamental practices remain consistent across all hydrangea varieties. This guide will delve into the key strategies for autumn care for hydrangeas, guaranteeing a lush and beautiful display of flowers in the warmer months ahead.

The Importance of Autumn Care for Hydrangeas
Whether your garden boasts mophead or bigleaf hydrangeas (Hydrangea macrophylla), smooth hydrangeas (Hydrangea arborescens), or panicle hydrangeas (Hydrangea paniculata), understanding autumn care is essential. Neglecting proper care or pruning incorrectly can jeopardise the health and beauty of these shrubs. Seven core practices should be integrated into your hydrangea autumn care routine: deadheading, pruning, fertilising, mulching, providing weather protection, and caring for container-grown hydrangeas.
To Deadhead or Not to Deadhead: A Personal Choice
Deadheading, the removal of spent blooms, is a task that can be performed in autumn but is not obligatory. It’s a matter of personal preference whether to remove these faded flowers. Deadheading won’t significantly impact the quality or size of next year’s blooms. For those who opt to deadhead, a sharp pair of shears is recommended, trimming the flower heads a few inches down the stem. Caution should be exercised not to cut too far back, as this might hamper next year’s flower production.
Pruning: A Delicate Task
Pruning hydrangeas in autumn should be avoided. The timing of pruning depends on the type of hydrangea and the season it blooms. Hydrangeas can be divided into two categories: those that bloom on old wood (formed in the previous growing season) and those that bloom on new wood (formed in the current year). Pruning at the wrong time can result in reduced or no blooms. This should be done right after flowering, while the latter should be pruned in early spring. Pruning hydrangeas in autumn, especially the wrong type, can risk removing next year’s dormant flower buds, leading to diminished blooms.
Fertilising Strategy
Fertilising hydrangeas in autumn is optional but can be advantageous if executed correctly. Natural granular fertilisers can be applied during this time, allowing soil microbes to process the nutrients during winter, enhancing spring growth. However, using synthetic fertilisers in autumn can be counterproductive, potentially leading to nutrient run-off and waste.
Manipulating Bloom Colours Through pH
Depending on soil pH, certain hydrangea varieties, such as mopheads, produce either pink or blue blooms. Altering the pH in autumn can be an effective method to modify bloom colours. Blue flowers indicate acidic soil, while pink flowers signify alkaline soil. Adjusting the pH through additives like pelletised sulfur or dolomitic lime can yield desired bloom colours, but it’s important to note that this technique doesn’t work for all hydrangea species.

Mulching for Winter Protection
Mulching in autumn offers several benefits, including maintaining consistent soil moisture and deterring weeds. Additionally, it serves as insulation for the roots during winter, safeguarding against harsh weather conditions. A 2- to 3-inch layer of mulch, such as shredded bark or arborist chips, is sufficient, but it’s crucial not to pile it against the plant’s base. This protective layer can also be composed of shredded fall leaves.
Shielding Hydrangeas from Cold
In colder climates, providing extra protection for hydrangeas during winter is essential. For species that bloom on old wood, preserving the buds from freezing is critical. Wrapping the plants with landscape fabric, burlap, or row cover can insulate and shield them from the elements, ensuring blooms for the following season.
Caring for Container-Grown Hydrangeas
Container-grown hydrangeas require special attention in autumn. Due to their exposed roots, they are more susceptible to freezing. Strategies like surrounding the pot with bubble wrap, moving the pot to a sheltered spot, or creating an insulated cage around the pot can prevent root damage during winter.
Utilising Remaining Flowers
Late-blooming flowers can be harvested for indoor displays or dried arrangements. Hydrangeas add elegance to cut flower arrangements, and drying them preserves their beauty for an extended period. Options include air drying, hanging them upside down, or even using sunlight for rapid drying.

Tidying Up for the Season
As autumn progresses, clearing debris from the base of the plant is essential. Removing fallen leaves, weeds, and dead flowers promotes a clean and healthy growing environment for your hydrangeas.
FAQ’s
The purple colour in hydrangea leaves during autumn is a natural response to decreasing daylight hours and lower temperatures. It’s not a sign of a problem but rather a sign that the plant is preparing for winter. The purple hues result from the concentration of anthocyanin pigments as chlorophyll production decreases. It’s a normal part of the plant’s life cycle. Proper care during this time includes continued watering, mulching, and potentially removing spent flowers. The leaves will fall naturally, and new growth can be expected in the spring. You can even use the fallen purple leaves for mulch or compost.
Conclusion
Hydrangea care in autumn lays the foundation for robust growth and stunning blooms in the coming summer. With practices like deadheading, appropriate pruning, fertilisation, mulching, weather protection, and attentive care for container-grown plants, you can ensure your hydrangeas thrive through the changing seasons. Each step contributes to these remarkable shrubs’ overall health and beauty, transforming your garden into a vibrant spectacle of colour year after year.