You think you’re doing a good thing. Your poor philodendron is looking sad and yellow. “You must be thirsty,” you say to the plant, and you run to get your well-used watering can.

The next day Phil is looking, even more, peaky, and with love, you douse it again. A few days later, Phil is dead. You murdered him!

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Everyone knows you can kill a plant by under-watering, but many people get overzealous in the other direction.

You can recognise an overwatered plant by its yellow leaves, brown tips, and limp appearance. A chronically overwatered plant also begins to shed its leaves.

Plant roots make no value judgments. They will suck up all of the water you provide them and pass them up through the stem to veins in the leaves. When the leaves are already saturated, the cells stretch to accommodate the extra water. Keep adding more and the cells will burst.

At this point, some of the roots will rot and die. Plants need a direct proportion of root to leaves, so if the roots die, an equal number of leaves will go.

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At some point someone might have told you that houseplants should be watered once a week. This is not true. A plant needs water when it is thirsty, and this varies by plant species, season of growth, and the relative humidity where the plant lives.

The simple way to determine if your plant needs water is to touch the soil. If it feels dry, the plant needs water. If you do not trust this tactile method, you can buy a moisture meter. Don’t leave the meter stuck in the soil all the time. Just poke it in when you think the plant might be ready for a drink.

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If you have overwatered your plant, the one way to bring it back is to bring the root to leaf ration back by pruning.

If you catch it in time, the remaining root system will recover enough to take care of the remaining leaves on the plant, eventually creating new roots and foliage.