When summer ends and you need to drain your swimming pool, what do you do?
Most homeowners don’t want to leave water in the pool, especially if it’s above ground. So the easiest and quickest option is to drain the water into the landscape.
But there are unintended consequences of taking the easy way out on this annual pool maintenance task.
Swimming Pool Water Harms Plants
Swimming pool water contains chemicals, especially chlorine, that can harm your trees and landscape plants when water drains and floods the area. Too much chlorine can damage tree leaves and other delicate tissues. Too much chlorinated water all at once can even kill trees.
It doesn’t take much chlorine for damage to occur. Some experts say the concentration threshold for tree damage can be as low as 0.5 parts per million.
Other factors related to tree damage from chlorine include the timing of the exposure, the amount of pool water trees receive, and if trees are still growing or are dormant.
Chlorine Damage in Trees
Research shows chlorinated pool water reacts with elements in the soil to form chloride compounds. When trees take up these compounds through their roots, leaves will look like they’re burned, something similar to leaf scorch. Leaves will show dry dead tips, edges and leaf veins. Some leaves may yellow, have stunted growth, and drop before they should. These are all signs of chlorine damage.
Some trees seem to be more susceptible than others to the chlorine in pool water. For example, the following trees have a high sensitivity to chlorine:
- Ash
- Box Elder
- Crabapple
- Dogwood
- Horse Chestnut
- Maples
- Mulberry
- Pin Oak
- Sweet Gum
- Yellowwood
In addition to the danger of chlorine toxicity, releasing thousands of gallons of pool water all at once can starve trees of oxygen or damage roots, making them more vulnerable to soil borne diseases. It takes time for pool water to seep into the soil, for trees get a drink, and to let the soil dry properly.
Five Ways To Drain Swimming Pools Safely
Take your time to drain the pool safely to protect your trees from chlorine damage. Here are five ideas to help you get started:
- Stop chlorinating your pool at least a week before you plan to drain it. This step allows the chlorine to dissipate naturally.
- Test the pool water before draining to make sure the pH level is between 7 and 8.
- Drain the pool slowly to allow water to absorb into the soil over time.
- Consider non-chlorinated pool water as grey water, not clean water. Test the water on a few inexpensive and replaceable plants before watering trees.
- Scoop buckets of pool water to leave in the sun until no chlorine remains (about 24-48 hours should do the trick). Use these buckets to water plants in other parts of the landscape.
What To Do If Trees Are Damaged By Chlorinated Pool Water
If your trees show symptoms of damage from chlorinated pool water, irrigate the area with clean, non-chlorinated water to help dilute the chlorine and leach it out of the soil.
If that doesn’t help (and it may not) then give us a call. We’ve seen a lot of trees killed this way and may be able to save yours.
