The Common Mistake That Could Kill Your Houseplants

For the second time in a year, I went on vacation abroad and my husband killed a plant. The worst part? He killed it with love – too much love, that is. He overwatered it.

What hurt the most was that it was a snake plant, i.e. the most indestructible houseplant we know of. It turns out one thing can destroy it, and it’s not what you think – not too much sun or too little airflow or temperature fluctuations (although all of this may affect its well-being to some extent). This is giving him too much attention, when he asks only to be alone. Too much watering, and not even draining, brought in my Sansevieria.

This was not the first time that excess water had harmed my houseplants. My ZZ plant, another one of those houseplants that thrive on semi-neglect, has started to get very droopy over the past few months. When I polled friends on Instagram to verify its near-collapse, the most common response? “You water it too much.”

I could have sworn I was doing the opposite all along and watering it down. Wasn’t its yellowing leaves and its dull growth the signs of this? My husband and I (ah, the painful realization that I’m not guilty) had clearly misinterpreted all of this. So I turned to an expert, Lindsay Pangborn, a member of Bloomscape’s Grow-How team, to learn how to better understand the needs of my plants. And why overwatering seems to kill more than . . . underwater. His best advice? Avoid watering on a schedule and instead assess your plant and its soil to know when to water. Read on to find out more.

Too often watered Continued of a problem that submarine?

Lindsay Pangborn: Yes I agree ! Overwatering is one of the leading causes of houseplant death. There’s a reason drainage holes in the bottom of pots are our top tip for plant parents, especially those new to this lifestyle. Mastering the art of watering can be difficult because it depends so much on the individual environment: factors such as light level, humidity, temperature, air flow, etc. can all affect how quickly (or slowly) your plant uses water.

So why does overwatering kill plants?

KG: When plants are overwatered, their soil can become saturated and their roots are starved of oxygen. Over time, the roots just can’t function, which is why some signs of overwatering look so much like signs of underwatering (ah!). This problem first manifests as plants with droopy leaves that do not straighten after watering. Leaves often begin to turn yellow and fall off the plant at later stages of overwatering.

Which popular plants are particularly prone to overwatering?

KG:- The Parlor Palm is one of the most popular plants prone to overwatering. It requires so little water that it can instead thrive on regular misting a few times a week to stimulate growth and prevent insect infestation.
– The Money Tree is another plant that tends to receive more water than necessary since its growth is dependent on seasonal changes. This plant prefers deep but infrequent periods of watering, especially during cooler months when its natural growth typically slows.
– Succulents and Sansevierias are also prone to overwatering, due to their tendency to thrive in dry conditions and their ability to store water in their leaves and stems. They tend to need more watering in the summer months when they are actively growing, compared to the winter months when they are often dormant.

Are there any plants that don’t mind being overwatered?

KG: Many plants can grow in water and are able to adapt to periods of flooding. In the houseplant world, a common type of plant that tolerates a lot of water is the carnivorous variety. Many carnivorous species are native to a bog environment, which means they like to grow in moss that is constantly moist and exposed to direct sunlight. The pitcher plant is a prime example and looks great in a pot or hanging basket near a south or west facing window.

How can we make sure we don’t overwater our plants?

KG: One way to make sure you don’t overwater your plant is to make sure your plant’s pot has a drainage hole in the bottom to allow excess water to drain out. Often these pots have a matching saucer to catch excess water and protect your furniture. A plant in a pot without drainage holes increases the chances of root rot and general damage/death from overwatering.

A plant will “tell” you when it needs water. Each plant and its setting is different due to variations in temperature, humidity and light exposure. The same type of plant in a different location may require watering at a completely different frequency. For example, Sansevierias in full sun and warm temperatures can be watered weekly, while Sansevierias in a low light and/or cold area only need water once every 4-6 weeks. For this reason, we never recommend watering on a schedule, and instead recommend evaluating your plant and its soil to know when to water. One tip I recommend for potties is to do the touch test:

  • Push your finger into the ground until it’s level with your mid-knuckle.
  • If the soil is wet, don’t water it and check it again in a few days.
  • If the soil seems dry, water your plants until the water runs freely from the pot’s drainage holes. Remove excess water and return the pot to an empty saucer.