We’re having a heatwave, a tropical heatwave…
Long, warm days lingering into balmy evenings, the sizzle of the BBQ, jasmine and lavender wafting delicious summer fragrance. As the thermostat ratchets up, all that lounging about in the sun is thirsty work but it’s not just plants that need a helping hand.
Enjoy the summer heat and learn all you need to know about how to care for your garden in a heatwave with Hedges Direct. Discover our quick, hot-weather gardening tips that will help you keep your cool, plus keep your garden in tip-top shape!
How to help lawns cope in drought
For most of us, lawns are a biggie in drought but grass is a survivor. Lawns are evergreen planting on a larger scale and most of the time pretty much take care of themselves, but even grass can suffer during hot spells. Except for fine lawns, domestic lawns are a blend of tough grass species that are designed to help them cope with dry conditions.
But once we head into extended drought or the dreaded hose pipe bans come in, how do you stop your lawn from browning?
The good news is that most established lawns can cope reasonably well with weekly watering but unfortunately, excessively dry or prolonged hot weather can scorch even mature grassy areas. Unless you have huge underground water harvesters or endless water butts, buff-coloured grass is something most gardeners learn to live with. Better news is whilst prolonged drought browns the surface of grass, underneath the roots are still alive and kicking so lawns normally green up with the first rain.
Established lawns enjoy a good drenching once a week soaking right through to the soil beneath which is far more beneficial than sporadic watering. It encourages grass to root more deeply letting it access water more easily. If the dry weather has caused the ground to bake hard, spiking the lawn with a garden fork will help the water soak through into the soil.
You might be surprised to learn that over-watering can make your lawn turf less drought-tolerant since it gets used to a lash of water and doesn’t root as deeply. Equally, warm, soggy grass provides the perfect conditions for disease and moss growth. Whilst moss may be undesirable under normal conditions, it’s a good thing in a heatwave as it’s great at hanging on to water and will help the lawn to survive.
Like any young plant, there’s no getting away from the fact that newly-laid lawns can’t cope with water shortages early in life. Without water, grass seedlings will shrivel and die and need almost daily watering to allow them to establish.
Once the grass knits together – a sure sign it’s growing well and its roots have settled in – you can reduce the watering to 3-4 times a week. Once it’s firmly established, you can drop your watering regime down to a weekly drenching.
Feel free to use water butts, harvested rainwater or recycled house water, but try to avoid any that contain chemicals or bleach.
Learn more about how to care for your lawn in summer with our guide.
With how to water your lawn covered, here are some extra tips for gardening in a heatwave.
Tips for gardening in a heatwave
1. Mow the lawn less frequently
Did you know that dry weather slows down grass growth? You may have noticed your lawn doesn’t have that lush growth spurt once the warmer weather arrives and that’s nature’s way of helping plants cope with water deprivation.
Raise the cutting blades on your lawn mower and mow less frequently to encourage deeper rooting to help lawns survive the summer sizzle. Shearing grass very short weakens grass making it more likely to die back.
2. Avoid using weed killer on grass
Whilst conditions are dry, it’s better to avoid using any weed killer that might cause further damage on an already stressed lawn. If you’re wedded to using weed killer, wait until the following spring to apply and, where possible, use a glyphosate-based formula that is less damaging to the soil as it becomes inert once it hits the ground.
3. Water plants in the morning or evening in hot weather
Should I cut my grass during a heatwave? Can you water grass in the sun? Will plants recover from heat stress? Should you water plants in the sun?
These are just some of the common questions we’re often asked at Hedges Direct, and whether you’re concerned about garden plants or lawns, the best time to water plants in hot weather is early in the morning, late evening or even in the middle of the night. (Great news for insomniacs!) That’s because cooler temperatures allow roots to absorb water more efficiently and ensure valuable water isn’t lost through evaporation.
If your watering regime is a daytime one, now’s the perfect time to make the switch to help plants maximise their water intake.
4. Only water plants that need it
Understandably, you’ll want to give your plants plenty of water during a heatwave, but some plants are far better at dealing with hot spells than others, so prioritise those that really need it.
- New hedging plants planted in the previous twelve months need frequent, consistent watering to establish but mature hedging, trees and drought-tolerant plants normally cope well without intervention.
- Generally, any silver-leafed plant can cope with extended dry spells, most hedging and roses are incredibly drought tolerant and established shrubs don’t mind being overlooked during your usual watering regime.
- Palms have built-in water reservoirs by storing water in their trunks so can probably go for weeks on end without water. However, curling or folding fronds are a sign the plant is trying to conserve water by reducing evaporation and a sure indicator their water reserves are running low, so give them a hefty drink.
- Keep an eye on lush foliage plants that are more likely to struggle in hot weather. Acer, Anemone, Astilbe, Delphiniums, ferns, Heuchera, Hydrangea and Phlox prefer cool, moist conditions and are more likely to suffer from heat stress. Mature plants won’t need watering every day, so during prolonged dry spells, think about watering every 2-3 days instead. Keep an eye on them – if you see signs of wilt, rolled leaves or swooning, up the water dosage.
5. Focus water at the roots directly
Like us, plants can suffer from heat stress and it affects a plant’s ability to photosynthesise – too much sunshine for too long a period impairs their ability to function and grow normally.
Symptoms to look out for include leaf loss, leaves folding or rolling, dry leaf edges, wilting, bolting or sun scorch.
- Don’t panic. Keep a sharp eye out for any of the above symptoms and react early enough, your plants should revive easily enough, but leave it too late and they might perish.
- The moment you spot signs of dehydration, water plants liberally at the base, preferably early in the morning or late at night to help the water get straight to where it’s needed most – the roots. By the following morning, you should see the leaves looking upright and bushy again, but those adversely affected can take a couple of days or more to recover.
- Tap-rooted plants are better able to cope with heat waves than shallow-rooted plants since they can draw on water found deeper in the soil. Tap-rooted plants include perennials such as mallow, Baptisia (false indigo) and vegetables, including carrots, parsnips, parsley and radishes.
- While sprinklers are labour-saving, a heck of a lot of water is wasted through evaporation, so by using watering cans, recycled water or hosing plants directly, watering will deliver maximum results.
To find out more about keeping your garden hydrated, take a look at our guide on how to water your plants.
6. Try not to water foliage or flowers to avoid leaf burn
Watering plants in full sunlight can lead to leaf burn or scorch. It’s better to wait until the sun goes down or get up early in the morning to carry out watering.
7. Add mulch to the soil around plants
Prevention is always better than cure. Mulch plants from early to late spring with a thick layer of organic matter applied around the base, (about. 2.5cm) is ample for most plants, trees and shrubs. This helps trap moisture in the soil and helps suppress weed growth that competes for water and vital nutrients. You can use decorative bark too but be mindful that it robs nitrogen (one of the key elements plants rely on for leafy growth) from the soil.
8. Move potted plants into the shade
Moving garden pots and containers into the shade helps them survive hot spells more easily. Soil in containers dries out quickly so providing shade helps them keep cool, allows water to be transported around the plants more easily and keeps them growing and functioning normally. You’ll still have to water, but not nearly as often.
- You might try adding water-swelling granules mixed with compost to your planters. The granules absorb hundreds of times their own weight in water and act as multiple mini-water reserves, which means you can spend more time enjoying your outdoor potted plants than fussing over them.
- The right plant, right place approach should see off the worst effects of a heat wave, so check out our recommendations for container shrubs for full sun and heat. Choose obvious sun worshippers such as canna or drought-resistant plants such as lavender and rosemary
9. Install a water butt or barrel to collect rainwater
Collecting rainwater is one of the easiest ways to store water for use in emergency heat waves and it’s free. Barrels, water butts and recycling household water, (sometimes called grey water) all help in the battle against heat stroke but avoid using water that has high bleach or chemical content.
10. Plant in the evening
If you’ve visited the garden centre and couldn’t resist the temptation of buying beautiful new plants, plant them in the evening once the temperature drops. Water each pot generously, let them drain before tapping them out and placing them in a planting hole. Give them another good drink before firming in the soil and provide a final dowsing for good measure.
Try to avoid transplanting young greenhouse plants into the garden during hot spells as they may struggle to settle in. It’s better to leave them potted in the shade until the weather cools in the evening. Don’t forget to give them a good watering-in.
11. Cover water features and ponds
Ponds can get weed infested during hot weather, so it’s a good idea to have a regular weeding session to remove excessive growth where practicable. Be prepared to top up small ponds and water features, they often evaporate more quickly in hot spells. Consider turning them off or reducing their running time to prevent water waste. A bale of barley straw will help keep larger ponds clear of algae.
12. Care for wildlife
Wildlife can suffer during extended periods of hot weather, so here are a few eco-friendly tips that will help reduce heat stress.
- If you’re a bird lover, leave out bird feeders stocked with seeds and top up bird baths daily if necessary.
- Our feathered friends like nothing better than a drink and daily dunk to help them stay cool. Water isn’t needed only by birds – other mammals like hedgehogs benefit from bird baths too! Make sure they aren’t too high up so they can get to them, or too deep so if an animal does fall in, they can still climb out.
- Another way you can help wildlife is by providing shade. Just like us, our pets and wildlife enjoy having some shade in hot weather to help them to cool down. You might consider building or buying an insect hotel to provide welcome shade. Cats and dogs naturally find shady places to rest.
- If you’re lucky enough to have visiting hedgehogs, leave out plenty of clean water for them to drink. Often when the ground is baked hard, they may have difficulty accessing their normal food sources, so leave out some meaty pet food which goes down a treat. (Don’t forget, any food left out may also attract unwanted vermin, so take a balanced approach.)
- Plant plenty of nectar-rich plants. Nectar is an essential food for bees and butterflies, so growing beautiful nectar-rich plants such as Mexican orange blossom or Weigela provide flying insects with essential nutrients.
- Unlike butterflies who flourish in warm weather, would you believe bees can suffer heat fatigue? A homemade sugar and water solution placed near flowering plants will help restore their energy levels.
Drought-tolerant plant ideas
One of the most effective ways of sailing through a heat wave is by growing drought tolerant plants. They look good, many are fragrant, and they positively thrive in the summer heat without needing too much water. Browse through our top ten favourites.
Bay is a wonderfully architectural tree as well as providing popular herbs for the kitchen with its grey-green aromatic leaves. They can be grown as a standalone feature, look fabulous in large containers as topiary and make elegant drought-resistant hedging, too.
The British have got a soft spot for box (Buxus) and no wonder! It’s smart, tough and versatile and can be clipped into almost any shape. Different species have varying leaf sizes so if you’re searching for a timeless, classy, dependable shrub, look no further.
Those heavenly blue flowers against a cloudless sky make Ceanothus an irresistible addition to any garden design. English or Mediterranean style gardens, cottage or country gardens all can find space for this gorgeous trouble-free, free-flowering evergreen.
Evergreen shrubs are a great way to add structure to any garden and they don’t come much better than Escallonia. Delightful tubular flowers in reds, whites and pinks smother the foliage from June to October and look fabulous in the winter landscape too.
Bluegrass is the height of contemporary fashion and is ideal for sunny courtyards, patios, balconies or larger family gardens. Blue-grey tufted arching semi-evergreen leaves add a touch of authenticity to Mediterranean and gravel gardens and they thrive happily in pots and containers for short-of-space gardeners. Tidy up scruffy leaves with a light haircut in spring or late summer.
Which of us hasn’t been seduced by the charming tangle and heavenly flower fragrance of honeysuckle? A perfect partner for climbing roses, it clambers over arbours, fences, trellis and walls. Pretty, tubular, rich pink-red flowers attract bees and butterflies, it’s winter hardy and most varieties can cope with light shade.
Lavender needs no introduction. It’s an eternal favourite and comes in so many different varieties with signature narrow, aromatic silver-grey leaves and flower colours from white, pink, red, lime green and deep purple. From compact to larger varieties, no self-respecting sunny garden should be without it.
Tall fountain-like feathery plumes guarantee pampas a spot in sunny gardens. Fashionable in suburban gardens in the seventies, the introduction of compact varieties has allowed smaller gardens to enjoy this fabulous prairie plant.
Surely one of the most popular drought-tolerant plants on the planet. The abundance of tiny powder blue flowers creates an enticing pale blue haze. Rosemary’s aromatic needle green-grey leaves are perfect for budding chefs and budding aromatherapists who love using it in homemade soaps and shampoos.
Arguably one of the most architectural grasses out there, admittedly, zebra grass needs a decent-sized space to grow. But if you’re looking to add elegant height, movement and texture to large mixed or long borders, Miscanthus should surely be top of your wish list.
Keeping your garden happy and healthy during a heatwave is easy once you have the know-how. Explore all our drought tolerant hedging or head over to our blog to discover more tips and tricks to keeping your plants in tip-top condition.