I garden in a warm climate, so avoiding outdoor chores midday, especially in summer, has been ingrained in my routine for years. Record-breaking heat waves are becoming the norm across the globe, so it’s a habit I recommend every gardener adopt.
Staying physically comfortable (and safe!) matters, but there are advantages for your garden, too. Timing your work before 11 a.m. helps plants absorb the hydration and nutrients they need to thrive.
What Happens to Watered Soil After 11 A.M.
The main reason to water early comes down to evaporation. When you apply water during the hottest part of the day, it evaporates before the soil has a chance to absorb it down to the roots, so the plant doesn’t reap the full benefits.
Oregon State University Extension notes that wilting during the hottest part of the day, followed by recovery in the evening and early morning, is a sign of heat stress, and that shallow-rooted plants dry out and wilt fastest. Deep watering in the early morning gives roots time to actually absorb moisture before the afternoon heat sets in, rather than losing it to the air.
The exception: If a plant is already wilted, don’t wait! Water it right away rather than waiting for a better time. The wait costs more than the timing does.
Prune and Fertilize Before 11 A.M. Too
Watering isn't the only chore that benefits from an earlier start. A plant already working hard to conserve moisture has less capacity to recover from anything extra—like pruning and fertilizing. OSU Extension experts advise against pruning during intense heat, since cutting away growth exposes previously shaded tissue to direct sunlight, which can lead to sunburn on parts of the plant that weren't hardened for it.
Stressed plants are also more vulnerable to damaging pests.
The same logic applies to fertilizing: pushing new growth during a heat wave asks the plant to spend energy it's using to survive, so it's better to wait for cooler conditions. Plant scientists say that heat stress limits a plant's ability to draw up enough water to support new demands, whether from a fresh cut or a fertilizer boost.
Why Morning Gardening Is Better for You
Take it from someone who has gardened through nearly 20 summers of heat: Mornings are easier on the body. By 10 a.m., the heat index in many regions of the country can climb past safe levels, and heat-related illness rises sharply once it crosses 90 degrees, according to North Carolina State Extension.
The catch is that gardeners often push through a task without noticing early signs of dehydration or heat exhaustion, like dizziness or nausea, until they've overdone it.
If early mornings don't fit your schedule, dusk works just as well. Either way, the goal isn't to power through the heat. It's to avoid needing to.
Debbie Wolfe is a writer, photographer, and author. She has contributed hundreds of home and garden articles and DIY tutorials to leading media outlets and retailers. Debbie covers all home and gardening topics and has published hundreds of DIY tutorials with step-by-step photography for leading home and garden media outlets.
