4 Heatwave-Proof Plants That Bounce Back Fast – and 4 That Need Immediate Help to Survive Soaring Temperatures
When a heatwave hits, it's important to know which plants can survive on their own and which ones need special care. Learn which ones are which with this list.
Summer heatwaves happen to most gardens. It’s more a matter of when and for how long rather than if it will occur. The aftermath of a bad heatwave can be devastating – drooping plants, crispy brown foliage, and even dead plants. But you can minimize the damage with some simple rescue care during and after a heatwave.
To make your rescue efforts efficient and effective, it helps to know the plants that like heat and the ones that do not. It’s the latter that will need your immediate attention, while the former will likely bounce back on their own. If you live in an area that experiences a lot of heatwaves – though, they’re getting more common even in areas with historically cooler summers – then you need to know which plants can revive themselves quickly and which ones need special attention.
I’ll reveal the toughest heatwave-proof plants to grow in your garden and the ones that need some extra care after multiple days of high temperatures.
Heatwave-Proof Plants
If you tend to get frequent heatwaves, it’s a good idea to include more of these plants that tolerate high temperatures and recover readily without your help.
1. Coneflower
Native perennial echinacea, also known as coneflower, is very durable in the heat. Good in zones 3 through 9, coneflowers love full sun and get through hot spells with their long tap roots that reach deep for moisture. 'Cheyenne Spirit' coneflower from Wayside Gardens is a fiery multicolored cultivar that looks stunning in the summer garden.
While your coneflowers might wilt a little in the most extreme heat, they’ll likely recover by evening. Floppiness is a way for the plant to conserve energy. You can help it recover better and faster with occasional deep watering.
2. Russian Sage
Russian sage, which can grow in hardiness zones 4 through 9, is exceptionally heat-tolerant. Popular for its silvery-green foliage and pretty purple flowers, this perennial actually prefers the heat and soil that tends toward dryness. Overwatering or growing in soil that doesn’t drain well are among the easiest mistakes to make with Russian sage.
During a heatwave, it benefits from its leaf color, reflecting more of the harsh sunlight than plants with darker green foliage. As with other heat-tolerant plants, Russian sage has long roots, especially if you helped it get established with deep watering. You can water it during a heatwave, but this plant will recover regardless.
You can get a classic Russain sage plant online from Fast Growing Trees.
3. Stonecrop
Stonecrop is a type of sedum, which is a group of succulent plants that do very well during heatwaves and can be grown in zones 3 through 9. They are prized for their fleshy leaves and flat clusters of small flowers.
They’re also popular for how easy they are to grow and how forgiving they can be of summer heatwaves. 'Autumn Joy' stonecrop, which you can get from Nature Hills Nursery, is one of the most popular and widely-available cultivars.
As a succulent, stonecrop stores water in its leaves. It also only opens the pores on its leaves at night, which means it doesn’t lose water during the day. These characteristics help stonecrop thrive right through the hottest days of summer. Not only does it not need your intervention, but overwatering it can cause more harm than good.
4. Lantana
Lantana is a hot-weather plant that is only hardy in zones 8 through 11. In colder climates, you can grow it as an annual flower. Lantana is popular for its bright, colorful flowers and its ability to survive and thrive throughout hot summers.
Lantana might wilt a little in the worst heatwave, but it will bounce back quickly. You can deadhead flowers after the heat has passed to encourage fresh blooms.
Watering might only be necessary if you grow lantana in containers. If you're looking for bright orange blooms to add to your container garden, 'Lucky Flame' lantana plants from Home Depot are just the thing.
Plants That Need Help in a Heatwave
Heat-tolerant plants make summer garden care a little easier, but you can still grow more sensitive plants. They just need some extra care to survive and come back to life after a heatwave.
1. Bigleaf Hydrangea
A lot of gardeners grow bigleaf hydrangea, which is hardy in zones 5 through 9, to enjoy its copious and colorful pink and blue flowers. Unfortunately, these small shrubs don’t thrive in extreme heat. The large, thin leaves lose water rapidly in hot and dry conditions, so they tend to wilt easily.
The flower buds can also be affected by heat, resulting in a hydrangea bush with no blooms. A lot of stress from heat can even reduce flowering the following year.
So what can you do? Water your hydrangea deeply each morning during a heatwave. Provide temporary shade with a shade cloth, like this one from Amazon, if your plants are in the sun in the afternoon. Keep mulch thick around the plants to retain soil moisture.
2. Japanese Maple
Most types of Japanese maples, which are hardy in zones 5 through 9, do not handle hot, dry conditions very well. Prized for their feathery, delicate leaves, heatwaves can quickly cause leaf scorch. Newly planted trees are particularly vulnerable.
If you grow a Japanese maple, water it deeply every day or every couple of days during a heatwave. If possible, plant your tree in a spot that gets morning sun and afternoon shade. Provide some late-day shade with a patio umbrella or shade cloth if necessary during very hot, sunny days.
3. Bleeding Heart
Bleeding heart is a unique perennial with heart-shaped flowers that hang elegantly from arching branches. It grows best in zones 3 through 9 with shade and rich, moist soil. These needs mean that it will not do well during a summer heatwave or drought. Too much heat can even trigger dormancy.
The best way to save your bleeding heart from the summer heat is to be proactive. Water it ahead of and during a heatwave. Provide extra shade if it currently gets too much afternoon sun. Once the heatwave is over, remove any leaves that didn’t survive with a sharp, clean pair of pruners like these from Fiskars.
4. Impatiens
Although they are native to warm climates and only hardy in zones 10 through 11, this popular summer annual doesn’t actually do well in extreme heat. Impatiens are prized for their summer-long flowers that bloom even in deep shade.
Too much sun, heat, and dry weather can quickly kill your impatiens without intervention. Keeping them well watered is the best thing you can do for impatiens in summer. Water impatiens in the ground at least once a day and those in containers twice a day.
You can also move potted impatiens into full shade during hot and dry spells. Putting containers on a plant caddy from Amazon makes them easy to move into the shade and back into the sun once the weather cools.
Not all wilting plants are in danger in a summer heatwave. Some will bounce right back, stronger than ever. Others need emergency care. Knowing which plants are more resilient will help you focus your time and attention where they are needed most.
