August is here and for readers who live in the northern hemisphere, the hot, dog days of summer have definitely arrived. August summers bring plenty of glorious sunshine, a late summer flush of gorgeous flowers, and of course, ample opportunities to work and play in the garden. But sunny, hot (and crazy hot) hot weather gardeningweather also brings potential health challenges for gardeners. Before heading out for another day of frolicking with the flowers, the bees, and the butterflies, consider these points:

Hot Weather Health Challenges

Our bodies work to keep us cool in three ways:

Sweating

  • Evaporation of Sweat: When our body heats up, sweat glands release sweat onto the skin. As the sweat evaporates, it removes heat from the body, cooling us down.

Blood Vessel Dilation

  • Vasodilation: When we’re hot, blood vessels near the surface of our skin widen (dilate) to increase blood flow to the skin. This allows more heat to be released into the environment.

Breathing

  • Respiratory Heat Loss: Exhaling warm air and inhaling cooler air can help regulate body temperature.

However, the combination of summer heat, high humidity, and sun exposure work in tandem to pose health challenges for gardeners. Why?

  1. On hot days, our bodies work harder to regulate and maintain a safe internal temperature.
  2. Sweating is impaired on days of high heat and high humidity because the air around us is already saturated with water.
  3. When blood vessels near the skin’s surface dilate to release heat, our blood pressure decreases. This in turn increases the risk of heat-related illnesses and injuries related to falls.
  4. We breathe faster and deeper because our lungs are trying to take in cooling air to support the extra workload placed on our bodies. Extra moisture in hot air decreases both the availability of cooler air and oxygen.
  5. While UV radiation is not directly affected by heat, higher temperatures can intensify the effects of sunlight on the body. On hot, sunny days, people are more likely to be exposed to harmful UV rays due to spending more time outdoors, and UV radiation from sunlight is a significant concern for skin damage.

Common and well- known heat-related illnesses include:

Heat cramps: Symptoms – Painful muscle spasms which usually affect the calf muscle, hamstring, or abdominal muscles. Treatment includes stretching the muscle and drinking fluids which also contain electrolytes (sports drinks). Interestingly, pickle juice is often the fluid replacement of choice for athletes and those in the know. Why? Because pickle juice is rapidly absorbed by the body and has high levels of sodium and potassium, essential electrolytes that help maintain fluid balance and proper muscle function. Also, the vinegar (acetic acid) and salt in the brine trigger a neuromuscular reflex in the brain to relax the cramp in the affected muscle.

Dehydration, heat exhaustion, and heat stroke: A progression of symptoms. At first, we experience thirst, heavy sweating, weakness, dizziness, nausea, and elevated heart rate. As the body continues to overheat, the individual may look flushed and feel warm to touch. Both sweating and urination may stop. Individuals who have heat stroke become irritable and confused and have temperatures of 104+. Seizures may occur and a coma may ensue. Dehydration/heat exhaustion leading to heat stroke is a life-threatening emergency. Treatment includes preventing these health challenges before they occur. If symptoms do begin: Move to a shaded area or an air-conditioned room and sit or lie down. Drink fluids with electrolytes. Cool the body by wetting the skin and clothes. Call 911 if symptoms of heat exhaustion appear to be progressing to heat stroke.

Is it Too Hot to Garden?

Because the possibility of developing a heat related health challenge is greatest during humid weather, I advise patients and gardeners to check the daily heat index, which is easily found on most weather apps or through the National Weather Service. The heat index (also known as the apparent temperature) measures how hot it feels when the relative humidity is factored in with the actual temperature. Usually, the heat index is not an issue for temperatures below 80 F. However, for temperatures between 90-105 F, the risk for health issues rises substantially. I would not advise working outside on days where the temperature is about 105 F.

How to Stay Safe and Keep Your Cool

  1. Hydrate and stay hydrated. Drink 2-4 cups of water prior to gardening, then remember to drink 2-4 cups every hour when outside.
  2. Wear light, cool, and non-restrictive clothing, and don’t forget sunglasses and a wide-brimmed hat which covers your face and neck.
  3. Apply a water-resistant sunscreen of SPF 30+ 30 minutes before going out to the garden and reapply every 2 hours.
  4. Take frequent breaks out of the sun.
  5. Try to get gardening chores done early in the morning or later in the evening to avoid sun exposure and the hottest temperatures of the day. I love gardening at dawn and dusk when it’s cool, quiet, and the birds and garden critters are starting/ending their day. Night gardening is also a wonderful option; gardens are free to embrace their romantic and magical personas in the moonlight. However, gardening at night also presents additional safety considerations due to lower light levels, nighttime animal visitors, etc.
  6. Know your medications and health limitations. Many common medications can impact our heat and sun tolerance. Unfortunately, these side effects are often not well known. For example, a variety of popular anti-depressants, such as those in the SSRI class, can cause heat intolerance in individuals due to their effect on the hypothalamus gland. A number of cardiac, diuretic, and anti-hypertensive drugs, such as bisoprolol, impair the body’s ability to produce sweat. Also, many antibiotics, acne medications, and sulfa-drugs cause hyper-sensitivity to sunlight. Individuals taking medications and/or have underlying health issues should self-educate and speak with their health provider for further information.
  7. Most importantly, listen to your body. If you’re feeling tired or a bit too warm, it’s time to take a break. The weeds can always wait another day.