When plants have too little water, leaves turn brown and wilt. This also occurs when plants have too much water. The biggest difference between the two is that too little water will result in your plant's leaves feeling dry and crispy to the touch while too much water results in soft and limp leaves.
If the soil is wet, it's overwatered - if it's dry, it's underwatered. Browning edges: Another symptom that can go both ways. Determine which by feeling the leaf showing browning: if it feels crispy and light, it is underwatered. If it feels soft and limp, it is overwatered.
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.)
Wilting. The most apparent manifestation of insufficient irrigation in plants is general wilting. Water pressure inside the individual cells cannot exert force to maintain the turgidity, which causes them to droop. Yellowing and browning.
One of the quickest, first signs of overwatering your plants is to observe occurs at the tip of the leaf. If the tip of the leaf is turning brown this is a sign of overwatering. Too little water will result in your plant's leaves feeling dry and crispy to the touch while too much water results in soft and limp leaves.
The good news is that most plants will bounce back between 7-14 days if they're given proper care (which includes rehydration). If this isn't possible because major damage was done or little healthy root system exists then expect about 2 weeks until improvement can be seen.
Remove any dead or dying roots and keep only the roots that are healthy. Water only when the soil is dry to the touch, but do not let it get too dry. You should also seize all fertilization at this point until the plant is healthy again. Treat with a fungicide.
Stop Watering the Plant
But stopping your watering is always the first step. If you're overwatering, you'll likely notice that the soil is wet, so you want to make sure that soil is bone dry before you're ready to break out the watering can again.
Poor drainage or improper watering
Water issues — either too much or too little — are the leading reason behind yellow leaves. In overly wet soil, roots can't breathe. They suffocate, shut down and stop delivering the water and nutrients plants need. Underwatering, or drought, has a similar effect.
Plants in containers dry out a lot faster than plants in the ground. Pots absorb heat, which can stress plant roots, and the soil in them dries out much faster than soil in the ground. Container plants generally need to be watered daily.
Signs of root rot are slow growth, mushy stems, and wilting, yellow, distorted leaves (especially when the plant has been well watered, as wilting leaves can also be a sign of a dry plant).
To dry out soil quickly, you can apply hydrated lime to the soil, add compost and then turn the soil thoroughly to aerate it.
Look out for signs of overwatering – including a limp plant, yellowing leaves, or dropping leaves. If you see these signs, test the soil with your fingers. It should be pretty obvious if it's soggy! Stop watering and let the soil dry out.
If you think your plant is overwatered, take a break from watering it. Otherwise, the problem will continue to get worse. Don't add more water to the pot until you're sure the roots and soil are dry. This can take several days, so don't worry if there's a big gap between waterings.
Wetting leaves.
Plants get their moisture through their roots, not their leaves. Direct watering to the soil surface and avoid wetting leaves because water helps spread some plant diseases. Use a watering wand to reach ground level or a soaker hose or trickle irrigation system to wet the soil rather than the leaves.
A yellow leaf has lost its chlorophyll (pigment) and it can't turn green again even after you correct the problem. Don't worry, if the plant regains its health, it's possible that new leaves will fill in during the next growing season. Growing plants is always a matter of patience.
As for the leaves that still have brown tips, you can snip the dead parts away with a pair of scissors without hurting the plant. For some plants that have long, strap-like foliage, such as dracaena or spider plant, make your cuts at an angle to imitate the natural shape of the leaves.
For almost all plants, you should water them only when the top inch or so of soil feels dry. An easy way to check if your plant needs watering is to follow the finger dip test. Never be tempted to over-water. Over-watering is equally as harmful as under-watering.
Hydrogen peroxide can help to control fungal growth and fungal infection, such as root rot, by preventing the growth of fungi. It can also help kill fungus and bacteria on plant roots.
If you catch the disease early enough, it is possible to rehabilitate your plant. You will need to take the appropriate steps to treat the root rot to give your plant a second chance. Unfortunately, if the root rot is left for too long and there are no remaining healthy roots, your plant can't recover.
The best time to water plants is in the morning or evening.
More importantly, watering at these times actually helps the plant retain water. If you water in the afternoon, especially during summer, the heat and sun are at their peak and the plant's water will evaporate instead of absorbing into the soil and roots.