Overirrigation is a typical mistake made by farmers, especially when soil moisture monitoring instruments are not used. The extra water you applied, which you assumed would help the plant grow even bigger, may be the cause of your plants’ wilting and yellow leaves. Here are several indicators that your plants are getting too much or too little water.
Your field has plenty of water but your plants are wilting
The roots of the plant absorb nutrients from the soil. Roots need a mix of water, nutrients, and oxygen to survive and develop for plants to grow optimally. The gaps between the soil particles should be filled with oxygen in the ideal situation. Overwatering fills the gaps between soil particles with water and pushes the oxygen out, decreasing the amount of oxygen available to plant roots. When this happens, your plants will wilt, giving the impression that there isn’t enough water even when the soil is clearly saturated.
Your plants have yellow leaves which turn brown and wilt
Plant growth suddenly stops, and leaves turn yellow, then brown, indicating either over or under-irrigation. Examine the leaves: if they’re crisp, you’re probably under-irrigating; if they’re mushy to the touch, you’re probably over-irrigating.
Leaves falling
In both overirrigating and underirrigating scenarios, leaves fall. The premature fall of both young and old leaves, as well as the failure of buds to open, is an indication of too much water.
Leaf blister
Excess water reaching the roots can also be seen in the plant’s top portions, such as the stem and leaves. When there is too much water in the leaves, they cannot withstand the stress and the water breaks out, resulting in leaf blisters.
The soil
Before irrigating, inspect the soil. If you can locate moisture from your previous irrigation cycle 5 cm/2″ below the soil surface, you may be over-irrigating. On the other hand, if the soil is so hard that you can’t get a screwdriver through it, you might be under-irrigating.
How to avoid over-irrigating or under-irrigating?
Irrigation management must considernot onlythe water delivered through irrigation and rainfall, but also how this water moves through the soil and the soil’s capacity to store and make this water available to plant roots. Pay attention to the structure of your soil and its field capacity. Plant development is optimal when soil moisture is around the soil’s field capacity, so the water level should be assessed and taken into account for irrigation scheduling and maintenance. You can keep an eye on your fields and check if your plants are healthy or stressed using modern technologies like Manna or Rivulis ReelView.
In addition to the above guide, it should be noted that in some cases you want to deliberately stress your plants via under-irrigation (e.g. reduced deficit irrigation regimes).
Disclaimer: The above is provided as general advice only. Every application is different, and your irrigation schedule should be developed to your specific requirements.
FAQs
Plant growth suddenly stops, and leaves turn yellow, then brown, indicating either over or under-irrigation. Examine the leaves: if they're crisp, you're probably under-irrigating; if they're mushy to the touch, you're probably over-irrigating.
How can you tell the difference between under and over watering? ›
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. Yellowing leaves: Usually accompanied by new growth falling, yellow leaves are an indication of overwatering.
How do you know if you're over watering your plants? ›
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). Wilting leaves combined with wet soil usually mean that root rot has set in and the roots can no longer absorb water.
What happens if you over irrigate? ›
Over-irrigation can lead to water-logging. What happens when the soil is soaked in too much water is that it becomes damp and almost swamp-like. Since water is usually in charge of carrying the nutrients that feed the plants, it is easy to see how and why too much water can do more harm than good.
How do I know if my grass is over or under watered? ›
Your lawn should be a nice, even, deep green. If it begins to fade to a dull or dry shade, like a brown, it could be underwatered. The confusion comes in since this is also an overwatering sign. If you also see sponginess in your soil, then the discoloration is from overwatering, not underwatering.
Which is worse overwatering or underwatering? ›
Overwatering your lawn is actually worse than under-watering because it will cause more damage. An under-watered lawn will struggle and die, while an overwatered lawn will not only kill off your lawn, but can also ruin the soils underneath.
What does overwatered soil look like? ›
Soggy soil will look dark and damp, and will hold its form when squeezed and compacted and will have a plastic consistency. If you squeeze darker soil in your hand, and it maintains that shape, your water is soggy.
How do you determine irrigation needs? ›
For all crops and for each month of the growing season, the irrigation water need is calculated by subtracting the effective rainfall from the crop water need. This means that in February the tomatoes need 69 mm of water, in March 123 mm of water, etc.
Am I over watering or under watering my plants? ›
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.
How long does it take for plants to recover from overwatering? ›
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.
Research has shown that excess water can increase weed pres- sure and create an environment favorable to diseases. Crop growth and yield can also be impeded when over-irrigation: disturbs the oxygen balance of the root zone, drowns roots, reduces plant water uptake, and thus stresses plants.
What is the risk of over irrigation? ›
The Long Term Impact of Over Irrigation
Not only does it damage the plants, but over-irrigation will also affect various different important balances in the soil. The pH balance, oxygen balance, and nitrogen levels will all be affected, influencing the fertility of the soil for the long-term.
What does excessive irrigation do? ›
Over-irrigation of landscaped areas flushes pollutants, including herbicides, pesticides, fertilizers, bacteria and any other pollutants residing on vegetation or in soil, causing dry weather flows of polluted urban runoff.
How to tell if a tree is overwatered or underwatered? ›
Your soil should be cool and moist. If it's sopping wet, you're overwatering. If your soil isn't drenched or sandy, roll into a ball. If it crumbles, your tree needs more water.
What does under watering look like? ›
Take a close look at the lower leaves on your plant. If your plant is under watered, the leaves will turn yellow then begin to curl around the edges.
Is underwatering worse than overwatering? ›
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.
