How to Garden in High Heat

Plants like it hot, but super-high temps can put a damper on any garden party.

Long spells of endless sunshine might seem like your garden's idea of a good time, but, like most things in life, moderation is key—even for plants. With all that sun can come high temps and a lack of humidity that leaves your flowers, veggies, and herbs wilted or dried up, as well as defenseless against disease and pests. That's no party at all! Don't worry: You can help prevent heat-stressed plants and keep your own cool, too. So, put on a wide-brimmed hat, grab your water bottle, and help your greenery stay, well, green!

Here's how to handle it when Mother Nature shows up with high temps and just won't leave.


1. Protect from Too Much Sun

Intense UV rays can break down the chlorophyll that makes plants green, so if they're overexposed to the sun their foliage may end up faded, scorched, or dry and brittle. In other words, sunburns can happen to plants, too.

How to protect them:

 Throw them some shade (the nice kind). Move container plants that typically bask in direct sunlight to cooler, shaded locales in the afternoon hours, and use lightweight covers to help protect your raised beds or in-ground gardens from hot, drying winds. Improvise with umbrellas, bedsheets, or any DIY solution that will still let air circulate around your plants. Pro tip: Materials that are light in color won't absorb as much heat.

 Lower their stress levels. Deadhead spent blooms and remove damaged fruit from vegetable plants so they have more energy for staying healthy. Hold off on removing burned leaves (with the exception of roses) unless you see signs of pests or disease, as they can help shade your plant. And of course, avoid planting anything new in unusually hot, dry weather.


2. Keep the Soil Moist and Rich

The soil your plants are settled into holds the nutrients, moisture, and air they need to grow up strong. If that earthy goodness becomes dry and depleted, there's nothing for roots to absorb and deliver to the rest of your plant. Yikes!

How to give them a boost:

 Start with the good stuff. Make sure you use a great quality soil from the start for the best defense against extreme heat. Fill raised bed gardens with Miracle-Gro® Raised Bed Soil, work Miracle-Gro® All-Purpose Garden Soil into the top 6 inches of in-ground gardens, or use Miracle-Gro® Moisture Control® Potting Mix in containers—each will help maintain just the right amount of nutrients and moisture no matter the weather.

 Establish nutrient-rich soil early on. You should take a break from feeding your plants during a heat wave or drought. However, to prepare them for conditions that could cause heat stress, regularly give them Miracle-Gro® Water Soluble All Purpose Plant Food (following all label directions) so they're nice and strong before the unfortunate weather arrives.


3. Quench Extra-Thirsty Plants

Your garden will dry out more quickly in hot conditions, especially in high winds, so keep them hydrated. H20 gives plants the strength to draw nutrition from the soil and turn sunlight into energy. As thirsty as your plants may be, though, always follow any local water restrictions if there's a drought. Pro tip: Harvest rainwater in the wetter months so you'll have water available for your plants no matter what.

How to quench their thirst:

 Give ‘em a long drink. Your plants will be thirstier than usual, so as long as there isn't a shortage, give them extra water if they need it. You can usually tell when your plants want more to drink by their wilted appearance, but don't be fooled: Wilting can be caused by heat alone. Always test your soil before watering by sticking your finger down straight down into it, a few inches away from plant stems. If the top inch of soil feels dry, you need to water. The soil in containers dries out more quickly than in-ground or raised bed plantings, so pay special attention to those.

 Be smart about water. Drip hoses and timers make it easy to efficiently moisten and cool the soil, providing a slow and steady water source for heat-stressed plants. If you water by hand, concentrate the water around the base of your plants. Keep going until you see puddles begin to form on the soil surface, then stop, wait an hour, and repeat to get soil thoroughly moist. You can also lightly mist plants with a garden hose fitted with a sprinkler attachment to cool them off in the early evening. Don't overdo it—a short shower will do.

 Retain moisture with mulch. When spread 3 to 4 inches deep, and kept about 3 inches away from plant stems and foliage, a layer of mulch, such as Scotts® Nature Scapes® Color Enhanced Mulch, helps keep the soil a steady, cooler temp, as well as retain moisture. Mulch also helps block sunlight, reducing the chance that water- and nutrient-draining weeds will pop up.


4. Stop Opportunistic Weeds and Pests

Heat-stressed plants have a harder time competing with weeds and fighting off non-beneficial bugs. They're already putting so much energy into protecting themselves from heat and sun that they're too tired to fight off the bad guys.

How to give ‘em a helping hand:

 Keep an eye on weeds. If given the chance, weeds will steal water and nutrients from your soil. Don't make your plants compete, especially in hot, dry weather! Remove weeds frequently, including any roots, so they don't take over.

 Watch out for insects. Your plants are too feeble to fight off bad guys like mites, aphids, caterpillars, and other harmful insects. And of course, garden pests aren't bothered at all by hot, dry weather. Hmph! Keep them at bay by plucking bigger pests off with your hands, hitting smaller ones with a blast of water, or spraying them with insecticidal soap.

Once the weather's back to normal, pick up where you left off with your usual gardening routine. You may not get a bumper crop of big, juicy tomatoes or as many beautiful flowers as you would in other growing seasons, but you can still enjoy the pleasure of nurturing a garden.

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