Friday, August 19, 2011

Friday’s Flower Pot - How To Prevent Over-Watering

The autopsy reports indicate that most houseplants are victims of over-watering. And their assailants are most often charged with involuntary plant slaughter because the majority of plant murders deaths are truly unintentional; the growers of these unfortunate leafy souls ‘didn’t mean to do it’. Those of us who have graduated from offender to caretaker agree that the killing of houseplants by over-watering is not done by maliciousness but by lack of knowledge and insufficient experience.

I’m sure you don’t feel like listening to me go on and on about this, so, I’m going to get right to the point of this article, which is a sharing of information on how to avoid over-watering. And if you’re interested in learning a little something about how to prevent this major blunder, stick around. If not, don’t come crying to me when your plant’s autopsy report reads: “Death by drowning” and you’re charged with involuntary plant slaughter. Or, in your case, should it be voluntary? The reason I decided to write up this article is because I receive a lot of emails from individuals whose plants have drowned or are drowning. And I hate to say it so bluntly but I’m going to anyway, so listen up folks:

Me: Plants don’t drown by accident; they’re drowned by their owners

You: ‘Wha...? Are you accusing me of...? I would never hurt my plants”

Me: “No, not intentionally. But you are doing it”

You: “Really?”

Me: “Um...yeah”

You: “Now I have guilt...” [sob]

Me: “Don’t. Guilt solves nothing. Learn how to water properly instead”

You: “How?”

Me: “I will make some suggestions”

You: “Golly gee. Will ya?” [dopey smile]

Me: “Sure will.

You: “Super Duper”

Me: [sigh] “Just please don’t talk like that, okay”

You: “Like what?”

Me: “Like...I don’t now. Like you grew up watching ‘Lassie’ or ‘Leave it to Beaver’ or ‘The Andy Griffith Show’ or some such thing. You know what I’m saying?”

You: “Okey Dokey”

Me: [sigh]

Alright, here are some ways to prevent over-watering...

1) Don’t Water Your Plants On A Schedule

One of the biggest mistakes people make is to create a watering routine in which plants get their thirst quenched on a fixed schedule. Watering all your plants every Saturday morning between vacuuming the house and doing the laundry may be convenient for you but it may prove hazardous to the health of your plants. There are way too many elements that affect when your plant needs to be watered – type and size of plant, growth rate, type of soil, location, temperature, humidity, season, container, light levels and on and on - therefore it is utterly impossible (and very detrimental) to place any plant on a fixed schedule.. Scheduled watering is a dangerous habit to develop so stay clear of that. Water your plants when they are thirsty – whenever that may be.

2) Don’t Use A Container That’s Too Big

When a plant is grown in a container that is larger than necessary, it will sit in more soil then needed. That excess soil will not dry out fast enough; it will stay damp for a long time and the roots of the plant will be forced to soak in that soggy mess for days on end. Roots soaking in water are deprived of air and they will begin to rot. Once the roots rot, say good-bye to your lovely plant. If your plant needs to be repotted, one size up, maybe two is the way to go. Don’t choose a pot that your plant will eventually ‘grow into’. Your plant will never grow into it because it’ll end up in the compost pile in the sky way before that. Bigger is not better, it’s deadly.

3) Don’t Use A Container With No Drainage Holes

It is possible to choose pots without drainage holes but it’s not very wise. Sooner or later, you’ll drown your plant. Even the most experienced houseplant owners have trouble managing houseplants – especially the ones that like to dry out very well between drenches - in such a setup. The problem with placing plants inside containers without drainage holes is twofold. 1) You can’t leach the pot now and then, which is important because it removes excess soluble salts and 2) it is extremely easy to over water and kill the plant (especially the desert lovers that turn to mush if overly-saturated one too many times!). Yet many growers buy containers without good drainage, which endangers sensitive roots.

If you have a pot with no drainage holes that you really like and want to use, the best thing to do is make holes in the bottom to drain excess water (you can drill through clay pots) or simply insert a plastic pot with drain holes inside it and pot the plant directly in that.

4) Don’t Use (Or Rely On) Gizmos & Gadgets

Many of you may object to what I’m about to say but I’m going to say it anyway:

Do not use a moisture meter to determine if your plants need watering.

Or better yet:

Do not rely on a moisture meter.

A moisture meter, as many of you already know, is a probe that you insert into the soil that tells you whether it’s dry, moist or wet. And although they can be helpful, they’re not necessary and certainly not always reliable. Even if you use one of these gadgets, you will still over-water your plants if you don’t learn how to care for your plants without it.

5) Don’t Use Soil That Doesn’t Drain Well

No matter how much experience you gain over the years growing houseplants, if you continuously use a potting soil that does not drain well, sooner or later your plants will lose some roots to rot and possibly die from over-watering. Because not only does a plant need food and water, its roots also need to breathe; good soil must have the ability to retain some moisture, be porous enough to allow drainage of excess water and be light enough to admit adequate air circulation. If you purchase a bag of commercial potting soil that is too dense, mixing in extra ingredients such as perlite, turface, pine bark, amongst other things, can help improve its quality. Better yet, surf the internet for a homemade soil recipe.

6) Don’t Let Your Plants Sit In Standing Water

After you have watered your plants, make sure that you dump any excess water that has accumulated in the saucer below. Never leave your houseplants sitting in standing water or they will develop root rot. There’s really not much else I can add to this point; it’s pretty straightforward.

Well, that’s about all I can think of for now. A couple of other things you should consider is watering less in winter and watering very carefully in cooler rooms (especially during the winter) where the soil takes much longer to dry.

And yes, it’s true that one of the most complicated things to master is watering, but because it’s so important to your plant’s health and survival, you need to get a grip on that watering can. But don’t despair if you haven’t quite gotten the hang of it yet; eventually you’ll get there. Just keep working on it – one plant at a time.


  1. Guilty as charged! I think of it as killing by kindness. I don't want those poor plants to be dry and thirsty. So I overcompensate.

  2. Good post, Martha! I'm going to cheerfully agree but disagree with you on the schedule. I agree that plants shouldn't automatically be watered once a week. But I do think it's important to check on them once a week to see what they need (if anything). Otherwise people forget, then they water haphazardly. If you can get beginners thinking in terms of a schedule, it can be a lot easier for them to develop a bond with the plants.

    I think your advice is better suited for people who know what they are doing with plants already, not beginners.

    Not that you asked for my opinion...

  3. It's funny to read this today when I just had a customer who praised me for the trick I used to keep her mother's passionflower alive. Her mother is a chronic over-waterer, so when the customer bought the passionflower for her this spring, I repotted it for her and put a layer of clay pellets in the bottom of the pot, a little higher than the saucer would be, so that even if she kept the saucer full of water, the soil wouldn't be in direct contact with it - seems to work fine so far! And it's lovely if people remember to thank you!

  4. @Debra: As long as it's not intentional :) It's tough to master watering houseplants; it takes a lot of experience.


    Good point, Liza. I think people should check up on their plants every week to see if they need anything, but they shouldn't water them if they don't need it. But they should also check up on some plants in less than a week's worth of time because small plants on warm, summer days may dry out within three days or so. It really does take experience - along with trail and error - to learn to water well.


    Ivynettle, that is a great idea! That works well for plants that rot easily from over-watering, like cacti and succulents, for example. Nice that the customer has thanked you.

  5. too many obvious do nots and not nearly enough do's. What is the formula for knowing. That is why we're here.

    1. Well, this post was about preventing over-watering, not how to water. It's possible I've written something about proper watering somewhere on this site.

  6. Helpful guide for me.Thanks a lot.