Keeping your hydrangeas thriving during hot spells

Nothing quite matches a hydrangea in full bloom. Whether you prefer the immaculate, gigantic flowers of 'Annabelle', the changing tones of the paniculata varietes or the generous, timeless macrophylla types, hydrangeas are a must-have in any garden design. They are also tolerant of coastal conditions, which makes them ideal for Irish gardens. Whether grown in a large pot or in the ground, they are showstoppers that keep the garden looking its best in late summer.

Hydrangea Paniculata. Photo by Annie Spratt on Unsplash.

The most important thing to know about hydrangeas? They love water. Yes, it is in the name. 'Hydor' is the ancient Greek for 'water'. So, how can you keep your hydrangeas thriving during hot weather when water resources are limited? Well, it all starts with good planting practices.

Where to plant

Choose a spot in partial shade for your hydrangea. Although hydrangeas can tolerate full sun, they will quickly wilt if it gets too hot, considerably shortening the flowering season. They can tolerate some shade as well, but try to provide four to six hours of sun a day, preferably in the morning or afternoon, when the sun is not as strong.

Soil

Soil preparation is a must. Since hosepipe bans are becoming more frequent, making sure that you provide the right substrate is essential.

If you are planting your hydrangea in a pot, choose a large container and use a good multipurpose compost. Add vermiculite or even water-saving crystals for optimal water retention. You can still add vermiculite to the soil when planting in the open ground, especially if your soil is quite sandy or dries out too quickly.

Use ericaceous compost or soil only for blue and purple hydrangeas; it will help keep the colours vibrant.

Mulching

This is the part not to skip! We can never say it often enough: mulch, mulch, mulch! It keeps weeds down and prevents evaporation. For hydrangeas, a wood-based mulch is ideal. Bear in mind that it needs to be 5 cm thick (about 2 inches).

Watering

Hydrangeas will need water every day in summer. So, it may be a good idea to install a porous hose or drip irrigation system (there are some for pots too!) connected to a digital timer. This saves a lot of time and water, as the water goes directly to the roots, minimising evaporation.

However, when a hosepipe ban is in place, be sure to keep a watering can with a rose handy so you can water gently at the base of the plant, allowing the water to sink into the soil.

Blue Hydrangea Macrophylla. Photo by Atul Vinayak on Unsplash.

Final thoughts

It is possible to have magnificent hydrangeas, even during hot spells. After all, you can see them growing in Mediterranean countries, where they can brave scorching sun and high temperatures! Simple preventative practices can go a long way when it comes to garden maintenance. The right spot, soil and mulch will keep your hydrangeas fresh for longer, allowing you to enjoy their blooms in the garden or later at home in a vase.