What to do with hydrangeas in May – 4 tasks that will give the blooms a boost and bolster your shrub's resilience

It won't be long before hydrangeas burst into bloom, but to help them stay their best, it’s worth knowing what to do with hydrangeas in May.

Figuring out the best time to plant hydrangeas is one thing, but if you've already got a shrub in the garden, this month is all about supporting them ahead of their flowering period. You'll need to exercise some caution around pruning (more on that shortly), but go heavier on the watering, for a start.

Here's what to do with hydrangeas in May for healthy, flourishing shrubs over the year ahead.

What you'll need

1. Water them

Hydrangeas are thirsty plants (they're also shrubs that thrive in wet soil), and in May, a steady watering regime becomes more important than ever.

‘May is a busy month for hydrangea care, with watering sitting at the top of the to-do list,’ says Julian Palphramand, head of plants at British Garden Centres. ‘Even well-established hydrangeas benefit from consistent moisture as the weather warms up, so keep a close eye on the forecast and step in with your watering can if things turn dry.’

There are a few ways you can reduce the amount of watering your hydrangea needs, though – which brings us to…

2. Mulch around the base

According to Julian, mulching can have a number of benefits for hydrangeas in May.

‘A layer of compost or other organic mulch around the base of the plant will help hold that moisture in while also keeping weeds at bay,’ he says.

RocketGro Organic Magic Mulch, available at Amazon, is peat-free and feeds the soil while conserving moisture and suppressing weeds.

If you’re keen to feed your hydrangeas with a fertiliser, you’ll need to choose the right kind…

3. Feed them the right ingredients

If you’re wondering what else to do with hydrangeas in May, you can add feeding to the list. In fact, you can begin feeding the shrubs from early spring – and it’s often a go-to task for gardeners hoping to revive woody hydrangeas.

Even for healthy hydrangeas, though, fertiliser can build resilience, promote greener leaves and even boost flowering. You’ll just need to watch out for certain ingredients.

‘If you plan to feed, go easy and steer clear of anything high in nitrogen, as too much of it encourages lush leafy growth that comes at the expense of flowers,’ advises Julian.

Westland Hydrangea High Performance Liquid Plant Food from Amazon contains a healthy dose of potassium for better flowering. It can be applied every seven to 14 days from March to August.

4. Prune with caution

There are several hydrangea pruning mistakes to avoid in spring, because trimming the wrong varieties can remove this year’s flowerheads – and no one wants a hydrangea that doesn’t flower.

Some will tolerate a light tidy-up, though – you’ll just need to identify the species you have, since the best time to prune hydrangeas depends solely on the type.

‘Some hydrangeas, such as panicles or smooth hydrangeas, can benefit from a light prune at this time of year because they bloom from new wood, so there’s less chance you’ll snip the bud,’ says Chris Bonnett, plant expert and founder of GardeningExpress.co.uk. ‘Gently shaping the plant and removing any old branches will help keep it healthy and well-structured.’

So, it’s best to focus on the three Ds – dead, damaged and diseased wood – rather than hard, regenerative pruning.

Knowing what to do with hydrangeas in May is crucial if you want your plants to flower well and stand strong over the rest of the year.