Usually underwatering a plant is less damaging than overwatering, which can cause additional problems like root rot and other diseases. But of course, if a plant is too dry it can shrivel up before you even realize it.
LPT - overwatering kills more plants than underwatering Source: BSc. horticultural science and former garden centre owner. More often than not, well intentioned gardeners (indoors and outdoors) kill their plants with too much H2O. The best thing you can do for (most of) your plants is let them dry out between watering.
Feel the Soil: The simplest way to gauge your plant's watering needs is by feeling the soil. Turns out that old trick of sticking your finger into the soil up to the knuckle has merit! If it's soggy or has standing water, you're overwatering. If it's dry an inch below the surface, it's time to water.
Over-watering can kill a plant more quickly than under-watering. Plants die when too much water in the soil causes the roots to suffocate and begin to rot. Often, the roots have already begun to succumb for rot before symptoms become obvious, and it's too late to treat.
This means you should always adjust your Pothos watering schedule, based on its growing environment. Remember that overwatering can lead to root rot, while underwatering will cause wilting and crisp leaves.
When a plant is first becoming overwatered, leaves turn yellow. If soil doesn't have a chance to dry out before you water again, leaves start to wilt. When overwatering is the problem, wilted leaves are soft and limp. (If too little water is the issue, wilted leaves are dry and crispy.)
When plants are under watered, they can usually recover within a few hours after receiving water. If they are overwatered, this can cause roots to rot, and the recovery process will take much longer.
It is best to water heavier less often than to water shallowly every day. If you have watered a plant for less than 30 seconds, you are probably guilty of this. Deep-watering encourages root growth. Plants need a thorough soaking if you want lush and vibrant growth.
Symptoms of overwatering indoor plants
The primary symptom of excess moisture is wilting or yellowing of lower and inner leaves. If excess water continues, plants may show other drought symptoms, such as scorch, leaf drop, and/ or plant death. Plants should be watered when needed.
Too much, too little or inconsistent watering are major contributors to houseplant decline and can cause brown tips on houseplants. Overwatering, the most likely cause, decreases the amount of oxygen available for root growth and creates an environment susceptible to root diseases and rot.
Overwatering means yellowing leaves, a general feeling of flop (science calls it wilting!), fuzzy soil, and a pot that feels like it could double as a weight. Underwatering shows itself with crispy leaves, that same sad droop, and bone-dry soil.
How to check for root rot. The main signs to look out for are: yellowing, wilting leaves, wet soil that isn't drying, black, wet roots, quickly declining health, and stunted growth.
One of the easiest ways to check if your plant needs watering is to stick your finger into the soil. This gives you a clearer indication of the soil moisture content than simply looking at the surface. You can reach 2-3in into the soil and feel how moist or dry the soil is.
If a plant is overwatered, it will likely develop yellow or brown limp, droopy leaves as opposed to dry, crispy leaves (which are a sign of too little water).
It is generally viewed as the better method because it is less likely to overwater your plants that way, but the drawback is that it takes longer than top watering. Can you overwater a plant by bottom watering?
Is Overwatering Worse Than Underwatering? Overwatering is as equally lethal as underwatering in plants. The colossal factor is blamed on the length of exposure: the more time the soil was soggy or dry, the more a plant is likely not to survive.
If the soil is still wet for more than a week, without outside contributing factors like rain or flooding, there might be a waterlogging or drainage problem. Watering clay soil is especially difficult, as poor drainage makes it especially prone to waterlogging.
Overwatered plants can sometimes recover on their own, but it depends on the plant and the extent of the overwatering. If the roots have rotted, the plant will likely not recover. However, if the overwatering has only caused the leaves to wilt, the plant may be able to bounce back.
Each plant has its specific needs, but as a starting point plants in pots with: 3-4 inch diameter containers need about half a cup of water. 5-7 inch diameter containers need about 1 cup of water. 8-10 inch diameter containers need about 2-3 cups of water.
Morning watering is actually preferable to evening watering as the plant has time to dry before the sun goes down. At night, water tends to rest in the soil, around the roots, and on the foliage, which encourages rot, fungal growth, and insects.
In fact, if you happen to be in the habit of watering every day or even every other day, you're adding too much water on your lawn, no matter what your neighbors might be doing with their own lawns.
Underwatering Revival
One of the first things you will want to try is soaking your plant in a saucer for 30 minutes to an hour. Just as with a dry sponge, a soak helps the soil to absorb water and expand. After soaking, remove your plant from its saucer and leave it for up to 24 hours to see if it has revived.
If the plant has been severely dehydrated or damaged, recovery can take longer, potentially several weeks to months. It will depend on the extent of the damage and the plant's natural growth rate. In some cases, full recovery may not be possible.