What To Know About The 3-Hour Gardening Rule Before Tending To Your Plants

Throughout the summer — and particularly in the midst of a heat wave — you should always follow the three hour-rule for gardening when going outside to take care of your plants. This rule states that there are three hours every day during the summer that you should avoid doing manual labor in the sun. Wherever you're located, the sun is at its hottest and most intense every day from 11 a.m. until 2 p.m. This is the time when the heat index is at its peak and UV rays are most dangerous.

Obviously, people should refrain from exerting themselves in the sun during these hours because the possibilities of heat stroke and dehydration skyrocket. However, it's also better for your plants if you avoid handling them during these hours as well. Plants can droop and wilt in the summer heat just like people can, and conditions are such during those peak sun hours that plants are incapable of withstanding too much handling. Whether planting, weeding, watering, or harvesting, the best times of day to be out and about in your garden are during the early morning and the late evening.

The best time to water your garden is first thing in the morning when temperatures are cool and the sun is still on its upward trajectory. This allows the most time for plants to absorb the water and its nutrients in order to stimulate growth. Watering your plants in the morning gives them fully saturated cells as the sun creates its daily arc in the sky, letting the soil have ample time to absorb the moisture and for photosynthesis to occur.

On the contrary, the middle of the day is the worst time to water your plants because that extreme heat evaporates the water too quickly for enough of it to be absorbed. Additionally, the sunlight is too intensely hot to invigorate the plants. Flora can get dehydrated too, but the fix to this is to water them significantly before the heat of the day so they're thoroughly hydrated before the scorching heat saps all their moisture away. The second best time to water your garden is in the evening, because the cooler temperatures will allow the water to be absorbed before it evaporates. However, because the sun is going down, it presents a higher risk of root rot as some water may not be absorbed or fully evaporate during the overnight low temps.

Pruning the garden is a task that some enjoy and some loathe, but few deny the necessity of doing it. When we prune leaves or dead buds off our plants, we are asking the plant to put its energy into growing and healing the areas that were cut. However, in the midday hours of 11 a.m. to 2 p.m., plants are under tremendous stress from the sun's heat and UV rays. They don't have enough water or strength to grow during that time, meaning your pruning efforts will be for naught.

In the same vein, fruits and vegetables are best harvested (and flowers best picked) when they are suffused with water, giving them a plumper, healthier appearance and allowing them to stay fresh for longer. During the high UV hours, plants' water levels are too low to provide that same level of freshness, meaning they'll wither, wilt, and go bad much too soon. Save these tasks — and all your other gardening chores — for the morning or evening hours to ensure a healthier garden.