Gardening under a hosepipe ban – is it still possible?

With water a scarce resource, gardeners should prioritise edibles and newly planted plants

Drought-tolerant planting will need to be embraced, but in the meantime a practical strategy can be adopted

Water is a finite resource, but until a hosepipe ban is announced we don’t think of its value because we’re rarely without water. Then when a shortage is announced every drop matters. Thames Water advises that we can use a watering can or a bucket, but how can we eke out a five-litre can and should we even be watering plants at all? How many buckets can we use? It’ still a lot of water if you’ve a medium-sized garden.

READ MORE: Thames Water announces hosepipe ban for 10.1 million people

A garden that has been built for a decade is now in peril after three heatwaves and will need careful management

Every drop matters

For gardeners, not being able to water expensive plantings also makes us question what is important. As a keen gardener myself, I have plants that I cherish, and I know that some aren’t all that practical.

I am also very attached to my green lawn (shown above) which is impossible to keep vibrant in 33 degree C and you’d be a fool to try. It is a terrible waste of water to run a sprinkler and I’ve never done that.

As the effects of climate change bite harder each year, I will have to make different choices for my borders, too, opting for plants that earn their place in the garden and don’t require so much water.

Suffering genuine drought stress, this birch tree and other dried-up plants will not recover

Casualties of climate change

That lush green lawn that contrasts so well with my trio of Betula utilis jacquemontii (birches with ice-white peeling bark) could instead be replaced by drought-tolerant plants, a mini-meadow with grasses or pebbly areas with sedums.

Though I am very careful with watering,  I still lost one of my three much-loved trees when we happened to be away during the second heatwave. When we returned, it was burnt to a crisp.

Birch trees that were reasonable choices for a domestic garden a decade ago might not be such a great option now as they are highly intolerant of dry, hot conditions, though they’ve been much used by councils planting in the public realm.

Erigeron karvinskianus grows in dry soil and full sun

For inspiration, I have looked at what local professionals are doing.

Award-winning garden designer and former Chiswick resident, Jane Brockbank, has created a gorgeous gravel zone and matrix planting in her Chapel project, which I love. Her studio’s approach embraces how plants coexist and interrelate in nature in an impressive way.

“I utilised a variety of plants in this garden including Sedum Purple, Erigeron karvinskianus and Salvia Viola Klose that will tolerate heat.”

During a hosepipe ban, you can still water vegetation in your garden, but you will have to use a watering can or bucket. In a medium to large garden (and there are many of these in leafy green Chiswick) that is a lot of lugging.

Instead of trying to water everything, you can choose what to save first.

Containers dry out quickly and need daily watering

Which plants are in greater need? 

Rosy Hardy, who exhibits regularly at The Chiswick Flower Market has a wealth of tips on her website that practical gardeners will want to heed.

“Not everything in the garden needs equal attention. In a [hosepipe] ban, triage is everything,” she explains.

She suggests prioritising vegetables, fruit and newly planted plants over the shrubs and perennials with an established a root system.

“Most established shrubs and perennials can cope with several weeks of drought – trust them!” she says.

Grouped together these Rudbeckia and Dahlias shade each other

Containers can be moved to safety

As plants in containers have no access to ground moisture, they dry out rapidly, and will need daily watering. To help them out further, Rosy suggests grouping your pots together.

“This raises the local air humidity around the plants and means foliage shades the compost surface, both helping to keep moisture where it’s needed.

“In summer, placing saucers or trays beneath pots is a useful way to capture any runoff and let the compost draw it back up, but do empty them a few hours after watering to avoid the roots sitting in standing water for too long.”

I also move pots into the shade to give them a break from the sunny areas of my garden. The plants that I moved out of the sun whilst on holiday were not as badly affected by the heatwave as others. I just grouped them in a row in the shade of my Photinia hedge.

A single water butt on a downpipe can collect hundreds of litres of water and, for extra water capture, connect more containers

Other sources of water

In times of water scarcity, it is important to collect every drop you can. We’ve had a water butt for years now and every time I use it, I feel happy that I’m using what nature provides more effectively.

The 150-litre vessel gets so quickly filled up in a downpour that I’m planning to install a run of slimline vessels to collect even more.

A water butt, available from DIY centres or garden centres, is relatively easy to install and captures precious rainfall that you can reuse on your garden.

In fact, rainwater is a great option for garden watering. It is naturally soft, low in minerals and has the right pH for most plants, including acid-lovers like rhododendrons and camellias. The minerals found in mains water, especially in hard water areas, are not ideal for plants.

The only downside of a water butt is that once empty, it will not fill up until there is more rain – and in a drought that’s not going to happen.

Using every drop: water from a vase, the washing up bowl and even the leftovers from a salad spinner; photographs Neal McDonald

Will grey water hurt the plants?

Another excellent source of water is grey water, which is water that you’ve saved from the kitchen sink, a washing machine cycle, a bath or shower. This water can be used on established shrubs and perennials but avoid putting on seedlings and edible crops.

Obviously avoid any water that contains bleach, disinfectants, dishwasher salt, or harsh cleaners. My plants don’t seem to mind a bit of washing-up liquid and I deliberately use the minimum of soap.

There are concerns with storing water for too long, so ideally use any collected water as quickly as possible to ensure its fresh.

Compost or wood chippings are ideal for spreading over flower beds

What else can I do?

I wish I’d mulched the garden back in the spring, but I was too busy and now I’m regretting that. Mulching will conserve moisture by reducing evaporation from the soil surface, which means you can significantly reduce watering your garden and keep plants healthy.

Ideally, you’ll spread a 5-7cm layer of garden compost, wood chippings, processed conifer bark, leaf mould or well-rotted manure in late spring, autumn or anytime for new plantings.

In the past, I have used my husband’s homemade compost from our two compost bins. This should be applied to moist soil otherwise you will lock the dryness in.

Wilted petunias perk up in the evening after being watered so are only experiencing temporary heat wilt

Do I really need to water?

After watching TV programmes like Gardeners’ World, I have been watering my garden less as is increasingly advised and – until the heatwaves arrived – that was working just fine. ‘Treat them mean to keep them keen’ is what Matthew Spratt, The Kew Plantsman, told The Chiswick Calendar.

He is a regular at The Chiswick Flower Market and propagates plants that he sells as well as being an expert on drought-tolerant species.

In hot weather, it is tempting to throw more water on a plant when you see it wilting but this can do more harm than good if you overwater and even cause root rot. I am trying to learn the difference between temporary heat wilt and genuine drought stress. Often plants do pick up in the morning and evening once temperatures drop.

Testing the soil a few centimetres below the surface with your finger can determine whether there is any moistness. If a plant persistently stays wilted into evening, then it is stressed. Look out for leaves that are dry, curled or papery and make sure you water at the base.

I water either early morning or evening,  following garden advice you can find on websites, but according to many experts it’s best to do it of an early morning. The temperature will be cooler then and there will be less evaporation. Do not water the garden in the heat of the day as it will be a wasted effort: water will not reach the plants’ roots before it evaporates.

Established plants surviving three heatwaves: Rosa Thomas A Becket; Gaura Belleza and Geranium ‘Jean Armour’

Right plant, right place

Despite the dried-out grass and the dying birch tree, I’m relieved that most of our garden is thriving in spite of the heat. Our roses, for example do surprisingly well. We rarely water the borders, preferring to give them a good soak when there hasn’t been rain in ages.

In future, I will be seeking out more drought-tolerant plants whereas before I just tried to follow the ‘right plant, right place’ philosophy, putting shade-lovers on one side and sun-lovers elsewhere, and avoiding ornamentals that will hate our clay soil. I did make the mistake of planting an Astilbe in our sun-baked front garden border, which was another casualty of the second heatwave.

Now I will need to change my planting ideas and embrace plant-types that I have never considered. I’ve never been a fan of grasses since one variety of grass – I called it bionic grass – overtook our borders and we had to work hard to dig it out.

Matthew Spratt, The Kew Plantsman, and other sellers at The Chiswick Flower Market, which happens the first Sunday of the month, will be able to help you with ideas for future-proofing your garden against drought.

Excellent for hot weather conditions: Perovskia atriplicifolia Blue Spire and sedum (hylotelephium)

Drought tolerant plants

“This dry weather is the death of the traditional British cottage garden,” says Matthew. “Unless gardeners in their droves go over to rainwater capture.”

Luckily, he has lots of ideas for plants that don’t need watering and many of these originate from Mexico, Africa or Australia so they can cope with the heat.

“I’ve got a wonderful plant on my allotment called Pennisetum orientale with pink flowers that thrives in full sun,” he says.

“Sedums or hylotelephium often have beautiful foliage and when they do flower they attract butterflies and bees.

“For colour, you could opt for pelargoniums because given a little water they will flower throughout the season.”

“Grasses are the most drought-resistant,” he says. “I sell a grass from Arizona that comes from the Sonoran desert. And there’s another one from Australia called Smoking Candles, I would recommend.”

Other attractive grasses he recommends include Muhlenbergia capillaris (pink muhly grass), Stipa gigantea (golden oat grass) and Helictotrichon sempervirens (blue oat grass).

Hardy Cottage Plant’s website is full of great ideas, too, including Verbascum, Eryngium, Salvia, Achillea, Gaillardia and Stachys – all plants that pack a punch in terms of either shape or colour.

Instead of choosing the highly popular Birch, consider other varieties such as Ginko biloba or Liquidamber

Trees that will survive

For trees, I will need to replace my much beloved birch and garden designer Jane Brockbank advises to stay away from replacing it with another identical tree.

“Birch generally are doing very badly so best to avoid – and they get planted all the time in London!”

She suggests Cercis (Judas trees), Liquidambers, Crateagus varieties (Hawthorns, but not just the straight monogyna), Robinias, Gleditsia and Ginko biloba.

It was a relief to consult a professional gardener as well as the expert horticulturalists of The Chiswick Flower Market. I’m encouraged by their generously shared knowledge that there are still plants to plant as the temperature soars.