Much of the state of Georgia is still in some phase of drought, including severe, even with all the rain we’ve had this year. Lake Lanier, the source of most of metro Atlanta’s potable water, is still down more than three feet from full pond level as of last week. So once we head into that long hot, dry spell that we all know is coming, how do we water our gardens, new plantings, and lawns?
The first thing to do is check local or county watering restrictions. Even now, many locales in the metro Atlanta area only allow hand watering with specific restrictions addressing what can be watered, along with when and how it can be watered. Be aware of those restrictions first, and then one can sort out how to make watering more effective and less wasteful.
We already know that the best time to water is very early in the morning, as close to dawn as possible, when the chance of water loss due to evaporation is not as great as it is during the hottest parts of the day. The second-best time to water is at dusk, but while it’s cooler than midday, there’s still a lot of heat hanging around in the soil, so more water may be lost to evaporation at dusk than during early morning. Watering without wetting the leaves of the plants with hairy leaves becomes an issue in midday, as the water beads basically create magnifying glasses on the leaves, exposing them to sunburn. Wetting the leaves during dusk watering exposes plants to fungus, since the leaves are unlikely to dry out before nightfall. Not all plants are adversely impacted by wet leaves overnight, so verify which, if any, plants are, and adapt the watering method accordingly.
Hand watering with a hose or watering can are probably the most common ways we give our veggies, perennials, and shrubs the moisture their roots need to support the rest of the plant. Using containers makes it easier to determine how much water has been added to the soil, but it’s also the most laborious way to water. Soaker hoses are the best way to reduce water loss due to evaporation or splashing onto impervious surfaces. There are many guidelines addressing how much water and how frequently watering is needed, based on specific plant needs. A good rule of thumb is that if the soil around the plant is dry at a depth of two inches, the plant probably needs watering. It’s better to water deeply and less often than to water frequently. Newly planted shrubs, trees, and veggies benefit from deep watering, using recycled bottles or buckets with several small holes that allow the water to percolate into the soil slowly.
The importance of mulching and groundcovers once the soil has been moistened becomes apparent once the temperatures soar or drop dramatically. Mulch preserves soil moisture while moderating soil temperatures close to the surface. This moderating effect keeps plant roots from both overheating and freezing. Groundcovers keep other plants’ feet cool and preserve soil moisture as well.
For those gardeners really committed to water conservation, consider installing rainwater collection systems. They range from simple rain barrels connected to downspouts to elaborate underground storage systems that collect larger quantities of rainwater. There are many resources on doing just this, and there’s no way to do those topics justice here.
Resources and further information:
This link refers to a story on the latest assessment of conditions at Lake Lanier.
These links offer tips on effective watering.
These links offer some ideas on rainwater harvesting.