In the field, the problems caused by heavy rainfall often extend far beyond the days when the rain is actually falling.

What really damages crops is often a rapid sequence of dramatic environmental changes:

For farmers, receding water makes the field look as though it is returning to normal. From a plant-physiology perspective, however, the stress is not necessarily over.

In fact, whether a plant can truly “come back” often depends on how quickly it recovers after the water recedes.

That is why, as extreme rainfall events become more frequent, farm management cannot focus only on drainage. We also need to ask:

This is exactly why rhizosphere microorganisms are receiving increasing attention in agricultural science.

Under normal soil conditions, pore spaces contain both water and air.

Roots do more than absorb water and nutrients. They also need a continuous supply of oxygen to maintain normal cellular respiration and energy metabolism.

When heavy rainfall keeps soil saturated for an extended period, water replaces the air in soil pores and sharply restricts gas exchange between the root zone and the atmosphere.

Research shows that oxygen diffuses through water at only a tiny fraction of the rate at which it diffuses through air. As a result, prolonged waterlogging can quickly expose roots to low-oxygen or even oxygen-deprived conditions.

The real problem with oxygen deficiency is that it directly changes the way plants produce energy.

Under normal conditions, roots rely mainly on mitochondrial aerobic respiration to generate enough ATP to support root growth, ion uptake, cell membrane function, nutrient transport, and many other root processes.

When the root zone becomes oxygen deficient, aerobic respiration is restricted and plants must rely more heavily on glycolysis and fermentation.

These pathways can still generate some energy temporarily, which is why crops do not always die immediately.

As flooding continues, plants gradually enter an energy-deficient state.

Studies indicate that glycolysis and ethanol fermentation can temporarily compensate for energy shortages, but under prolonged flooding, lactate, ethanol, aldehydes, and other anaerobic metabolites may accumulate and eventually cause cellular injury or even death.

So a green onion that still looks green above ground does not necessarily have healthy roots below. In many cases, the damage starts in the root zone first.

Roots are not simply responsible for “taking up water.”

They also support nutrient uptake, plant signaling, interactions with rhizosphere microorganisms, and the supply of resources needed for above-ground growth.

Once root activity declines because of oxygen deficiency, the above-ground parts of the plant are gradually affected as well.

Flooding is often associated with stomatal closure, reduced chlorophyll, leaf yellowing, and lower photosynthetic activity. As waterlogging continues, carbon assimilation and growth can decline further.

That is one reason plants can be especially vulnerable after the water recedes.

It may seem intuitive that reactive oxygen species should be less likely to accumulate under oxygen-deficient conditions.

In reality, plant responses are more complex.

Studies show that under flooding and low-oxygen conditions, plant cells may still accumulate reactive oxygen species (ROS), including superoxide radicals, hydrogen peroxide, and hydroxyl radicals.

At moderate levels, ROS are important signaling molecules involved in stress responses and regulation.

But when ROS production becomes excessive and the antioxidant system cannot remove them quickly enough, oxidative damage can occur.

The ability to regulate ROS effectively is therefore an important part of flooding tolerance.

One feature commonly observed in more flood-tolerant plants is the ability to maintain higher activity of antioxidant enzymes such as SOD, CAT, POD, and APX during stress, helping keep ROS within a more manageable range.

When standing water drains away and soil is exposed to air again, oxygen begins to return to the root zone.

On the surface, this looks like good news.

But for the plant, it means that a metabolism adapted to low-oxygen conditions must switch back to normal aerobic metabolism.

This process is known as reoxygenation.

Research indicates that plants must continue regulating ROS and stabilizing photosynthesis and cellular metabolism during reoxygenation. The ability to manage this transition can directly affect whether a plant successfully recovers from flooding stress.

Roots still need time to restore respiration.

Cell membranes must regain stability.

Water and nutrient transport must be re-established.

Photosynthesis must gradually return to normal.

This is a common situation in Taiwanese agriculture.

Several days of continuous heavy rain.

Fields remain waterlogged for an extended period.

Then the weather suddenly clears and high temperatures and intense sunlight return immediately.

At this point, plants face a particularly difficult situation:

Strong sunlight and heat increase leaf transpiration and metabolic demand, while roots affected by flooding may still have limited capacity for water uptake, nutrient transport, and energy supply.

Current research provides strong evidence for the relationships among flooding, oxygen deficiency, reoxygenation, and ROS. Direct research on the specific field scenario of immediate post-flood exposure to high heat and intense sunlight is still comparatively limited.

This also reflects a common field observation: some crops do not die while the field is still flooded, but begin to yellow, weaken, lodge, or decline rapidly several days after the water recedes.

This does not mean that drainage makes the situation worse. Rather, damage accumulated during the earlier root-zone stress may become more visible and more severe during the next stage.

Another issue farmers know very well is this:

Disease problems often appear after heavy rain.

This is not a coincidence.

Plant disease typically develops when three conditions occur together: a pathogen, a susceptible host, and an environment favorable for disease development.

Prolonged flooding can alter two of these conditions at the same time.

On one hand, high humidity, low oxygen, and waterlogged conditions may favor the survival or infection of certain pathogens.

On the other hand, plants weakened by oxygen deficiency, energy shortage, and oxidative stress may become more vulnerable to pathogens they could otherwise resist more effectively.

Research suggests that some plant pathogens can take advantage of high humidity, low-oxygen conditions, and weakened plant defenses. In this way, abiotic stress and disease are often not independent events, but interacting pressures that can amplify one another.

Another important area of research is the role of beneficial microorganisms under combined “stress + pathogen” pressure.

Some PGPM may not only support plant growth, but may also reduce opportunities for pathogen establishment and infection through competition for nutrients and space, direct antagonism, and induced systemic resistance (ISR).

As a result, plant-microbe research is beginning to move beyond a single question:

“Can microorganisms help plants tolerate flooding?”

The broader question is becoming: “Can microorganisms improve overall resilience to both flooding and subsequent pathogen pressure?”

For real-world agriculture, this is even more important.

Farmers rarely face only one stress at a time.

When discussing stress tolerance, it is easy to reduce the question to one simple indicator: did the crop die or not?

From a production perspective, however, that standard is too low.

Even if a crop survives, ten days or two weeks of growth stagnation—or a failure to return to normal yield potential—can still represent a major loss for growers.

Researchers increasingly evaluate flooding tolerance using indicators such as root vitality, recovery of photosynthesis, antioxidant capacity, compensatory growth, and final yield recovery.

Some studies even use the term “post-stress compensatory growth” to describe a plant’s ability to resume growth after flooding ends.

Studies of flood-tolerant plants also show that truly resilient plants do more than simply survive flooding—they recover faster and more strongly after the water recedes.

For growers, the most meaningful question may be: after the same flooding event, which crop recovers faster?

At this stage, a field case alone is not enough to conclude that:

RichFarm Booster produces these results through one specific physiological mechanism.

However, current research on beneficial microorganisms and flooding stress provides a scientifically reasonable basis for further investigation of these observations.

The result may not come from a single effect, but from the combined contribution of multiple factors:

At Rolling Greens, we do not position RichFarm Booster as:

No biological product can replace proper drainage or eliminate extreme weather.

A more appropriate positioning is:

Extreme rainfall is not going away.

The future of agriculture is not about dealing with only one type of stress, whether drought or flooding.

Plants must continuously adjust their physiological state within a very short period of time.

That is why stress resilience should not be understood as “never being damaged.”

This is also the management philosophy Rolling Greens hopes to support through RichFarm Booster.

The goal is not to wait until flooding occurs and then start trying to rescue the crop.

It is to build healthier roots and a stronger rhizosphere microbial environment during normal cultivation.

Because when the real storm arrives, a crop’s ability to endure it may already have been shaped long before the rain began.