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Ever had this happen? It is the end of the rainy season, the sky is gray all day, the room feels damp, and suddenly the Monstera on your desk turns yellow and dull even though you water it the same as always. This article explains root rot in Monstera deliciosa and Philodendron. The short answer: late rainy season brings high humidity and low light, so soil dries far slower than usual and roots are at risk. You can prevent it by checking soil moisture before watering and using a loose, well-draining potting mix.

Why Plants Are at Risk of Root Rot in the Late Rainy Season

Roots need to breathe. When soil stays soggy for too long, water replaces the air pockets, roots run short of oxygen, and fungi and bacteria move in. Roots that should be white and firm turn dark brown, mushy, and smelly.

The 5 Most Common Causes

High air humidity Soil in the pot dries noticeably slower, but we keep watering out of habit.
Less light Cloudy days and rooms with little window light make plants use water more slowly.
Compacted potting mix Old soil collapses, packs down, and holds more water than needed.
A pot that is too big Extra soil holds water that the roots cannot reach yet.
Standing water in the saucer Roots sit in water from below without us noticing.

A common myth is that yellow leaves mean the plant is thirsty. In this season, yellow leaves are more often caused by too much water. Adding more will make things worse, faster.

How to Check Soil Moisture Before Watering

You do not need any gadgets. Your hands and eyes are enough.

3 Methods That Really Work

Finger test Push a finger 3-5 centimeters (about one knuckle) into the soil. If it still feels cool and damp, do not water yet.
Lift the pot A freshly watered pot is heavy and a dry one is clearly lighter. Lift it right after watering and remember the feel.
Wooden stick Push a wooden stick into the soil and pull it out. If damp soil clings to it, the bottom is still wet.

For Monstera and Philodendron, the rule I have used in my nursery for over 10 years is to let the top 2-3 centimeters of soil dry out, then water thoroughly until water runs out of the drainage hole, and always empty the saucer afterwards. In late rainy season the interval may stretch to roughly every 7-10 days, but follow the soil, not the calendar.

A Loose, Well-Draining Potting Mix Recipe

Monstera and Philodendron are climbers whose roots cling to big trees in nature, so they like loose media that lets air through, not heavy, soggy clay.

Basic Recipe for Beginners (by volume)

Material	Ratio	Purpose
Loam or general potting soil	2 parts	Provides nutrients and anchors roots
Pine bark or small bark chips	1 part	Creates air pockets and does not collapse easily
Perlite or small lava rock	1 part	Improves drainage and keeps soil loose
Chopped coco fiber or charcoal	0.5 part	Holds just enough moisture and aids aeration

If your room is very humid, or you keep plants in an air-conditioned office with little light, add a bit more bark and perlite. The looser the soil, the more forgiving it is when you accidentally overwater.

Repotting Without Shocking the Plant

Choose a pot only 1-2 inches larger than the old one, and always with drainage holes.
Gently slide the plant out, shake off old soil, and inspect the roots. Healthy roots are white to cream and firm.
If you find rot, cut away all black, mushy parts with clean scissors and let the cuts dry briefly before repotting.
Fill with fresh mix, water lightly, and place in bright indirect light. Hold off on fertilizer until new leaves appear.

Placing Plants on a Work Desk in Late Rainy Season

A desk with a monitor and stacks of documents often has poor airflow. Try moving your Monstera closer to a window with bright light but no harsh direct sun, and leave space around it so air can move. If you have dogs or cats, be a little careful: both Monstera and Philodendron contain calcium oxalate, which irritates when chewed or eaten, so keep them on a high shelf out of reach.

If you would like to start with plants already potted in a loose mix, PAMA The Gardener is ready for you to adopt one for your desk, packed securely and arriving with strong roots.

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How can I tell if roots are rotting?

Check the roots and soil. Rotting roots turn dark brown or black, feel mushy, and smell musty. Above the soil, leaves yellow and droop and stems go soft even though the soil is wet. If in doubt, slide the plant out of the pot and look at the roots.

How often should I water a Monstera in late rainy season?

Water when the top 2-3 centimeters of soil are dry. In this season that is usually every 7-10 days, but the real interval depends on light, pot, and potting mix, so always do a finger test first rather than watering by the calendar.

Can a plant with root rot be saved?

Yes, if some white or cream roots remain. Remove all rotten roots, repot into fresh loose mix in a smaller pot that fits the remaining roots, and hold back on watering at first. If the stem is still healthy, you can also take cuttings to keep the plant going.

Can I use ready-made potting soil on its own?

You can, but it is better to amend it. Many bagged soils hold a lot of water and collapse quickly. Mix in pine bark and perlite, at least one third of the total volume, to improve drainage and aeration while the weather is still damp.