It's curious that no matter how accomplished we are at growing plants, most of us have killed at least one by overwatering it. In fact, overwatering is probably the number one problem we see. The best plant caregivers are not infallible; we all make mistakes. However, a plant that's been overwatered does not necessarily suffer a death sentence—there are simple ways to treat this unfortunate mishap.
The roots of a plant absorb air, water and nutrients to support the stems and leaves above. Excessive watering cuts off the air and the roots begin to suffocate, rot and eventually die. Fungus and mold in the soil increases, causing trouble for the remaining healthy roots. The most common signs of overwatering are wilting leaves and a pot that feels heavy due to soggy soil. Yellow leaves, mushy or loose bark on the plant stems and molds that appear on the top of the soil are also indicators of overwatering.
It’s possible to correct an over watering issue if the plant hasn’t been stressed too severely. Firstly, make sure your pot is draining and take the plant out of the direct sunlight, as this will further stress your plant. Do not feed your plant when it is enduring this stressed state. A radical approach to correct a valued specimen is to take your plant out of its pot and set it on a layer of newspaper or something equally absorbant. The newspaper will act as a wick, pulling water down through the root ball. One may need to replace the newspaper multiple times. Also, do not squeeze excess water from root ball, as this can cause further damage to fine root hairs. Be forewarned that after a plant has been severely stressed in this manner, it will not perform to the best of its potential and may not recover to its original state of health.
Once this step is complete, remove any dead or dying foliage or stems that appear to have rotted. They will be easy to identify, as they can be quite putrid smelling. Use a sharp hand pruner to cut away stems or branches that have loose bark or that are wilted and don't perk up after the above procedures have been completed.
Next, you will want to remove the soil from the roots carefully so as not to cause further damage. Repot the plant into fresh new soil and water the roots in gently; be careful not to soak the plant. Use a plant food that contains less than 1% hydrogen peroxide. (Follow the direction stated on whichever product you choose.)
Peroxide is great for getting oxygen into the plant's root system. Refrain from adding fertilizer at this time; forcing a plant into growth by fertilizing it only stresses the plant further and the roots are damaged and strained already. There are enough nutrients in the soil to help the plant along—the roots need to rest and recuperate, not work harder. Never pot plants directly in non-draining containers. If you do use these types of pots, leave your plant in its drainable pot and then place that into the decorative container. When you water the plant, remove it from the non-draining container and place it in the sink. Let it drain completely before placing it back in the decorative pot. Also, never let a plant sit on the collected water of a saucer. Discard any water that remains on the saucer 30 minutes after watering.
Overwatering your plants can be a problem of the past if you learn to read the soil. Don't be afraid to stick your finger into the potting medium. Study the soil and how it appears in your hand. If it's moist, it will likely appear black and will stick to your finger. When the soil is dry on top, don't arbitrarily add water, instead, stick your finger down deeper into the soil. If there is moisture below, wait a few days and recheck. The soil should be dry about 25% of the way down the pot before you water again.
Familiarizing yourself with your plants' watering instructions and following the advice given can reduce your chances of damaging them by overwatering. Getting to know your plants' needs intimately should give you the confidence to continue caring for them with ease. How do you know when it’s time to water? The only way to know for sure is by physically checking your soil moisture. It’s vital to do a touch test, when it feels dry 1-2 inches into the soil, it’s time to water. Actually lifting your pot to check its weight is also a sure fire way to check your moisture levels, as the water weight in a wet pot will be significantly heavier than a pot with dried soil.
As gardeners become more experienced, they develop a sixth sense about when and how much to water as the parameters are always changing. For instance a large plant in a sunny windy area will need more water and more often than a plant that isn’t as large and in a cooler area. The rule of thumb is you want your soil to be like a moist chocolate cake. Not soggy and not dry. Always be evaluating your watering needs to avoid problems that can quickly kill a plant or garden.