This Friday, May 30th, is National Water a Flower Day. Sounds simple enough, doesn’t it? Or maybe it isn’t. Improper watering is probably the number one killer of houseplants—and garden plants, too.
We’re so concerned about keeping plants watered, that we often forget they also need air. Yes, plants do breathe!
Let Your Plants Breathe
During the day, part of photosynthesis involves plants absorbing carbon dioxide from the air and releasing oxygen. At night, they absorb oxygen and release carbon dioxide. This is how they help to “clean” the air.
Leaves “breathe” through tiny little holes, called stomata, in the leaves. Roots get air from tiny air spaces in the soil. Plants that live in water actually have air spaces in the roots. Most plants don’t have air spaces in their roots so rely on air spaces in the soil. Water-logged soil does not have air spaces, hence plants literally drown.
How to Water the Correct Way
To correctly water requires finding out what a plant needs. As a rule of thumb, plants with thick fleshy stems and/or leaves (most cacti and succulents, etc.) are native to areas that are dry and so should be allowed to go almost, if not completely, dry when grown in pots—or in the ground. Plants with thin delicate foliage (ferns, etc.) should be kept moist, drying out only at the soil surface. Most other plants are somewhere in-between. That said, with the exception of water plants, almost every other plant should at least surface dry before watering.
When you do water, water thoroughly so water gets all the way down to the entire root ball—not just the ones at the top! In pots, water until water trickles out the bottom. If the plant has gone so dry that it has begun to wilt—or if the plant is potbound and the roots have pulled the soil away from the side of the pot, then allow the plant to soak for ten minutes or so to absorb the water they need. DON’T allow soaking longer than that.
Outside, while seedlings and young plants may need water every day or two, most mature plantings need no more than one to two good deep waterings a week (depending on what Mother Nature does). It’s most important to NOT rely on sprinklers to water! Sprinklers put water where we DON’T want it—on the foliage. With our high summer humidity, we’re already at risk of fungal problems. We don’t need to invite problems by keeping the leaves wet, too.
A Soaker Hose Can be Your Best Friend
Soaker hoses can be a gardener’s best friend—putting the water at the soil level—and not all over the place! Plus less water evaporates, so it is definitely better for your water bill. The way to tell you’re watering correctly is to place your soaker hose where you want it—then tuck a couple of cereal bowls under it. Turn it on and see how long it takes to fill the bowls with an inch of water. That’s how long you need to leave the sprinkler on when you water. You can also water with a hose, if you want, just be sure to keep the water at the base of the plant.
Watering correctly greatly improves your chances of being successful in whatever you’re growing. Maybe May 30th should really be called Water a Flower Correctly Day…
Thanks for your article. What about a very mature snake plant planted in a very deep planter?
Jan, snake plants like to go almost completely dry between waterings. If you can get your finger in the drainage hole at the bottom, the soil should feel almost completely dry to the touch. If you can’t get your finger in the drainage hole, a water meter stuck as far down as it can go could help. Lacking a water meter, an unpainted wooden dowel stuck in the soil as far down as it can go and left for 15 or 20 minutes then checked. If the wooden dowel is dry all the way down, then water. I’m hoping you do have it in a container with a drainage hole….
Hi Bonnie,
Question: I have 2 Lillies inside in pots and the leaf’s are getting brown and brittle on the edges. I have tried to adjust watering. Given them more water and than tried less water, same result. Any idea what I am doing wrong?
Do you know what kind of lilies they are? Asiatic Lilies and Oriental Lilies are bulbs and best grown OUTSIDE. They should be planted directly in the ground in a sunny area where they will grow for the summer, then go dormant in the fall and grow again next spring. They do not make good indoor plants. If they are bulb lilies, then they may be turning brown because they are indoors.
Kristina, another thought. Are these Peace lilies?
Hi
Thanks for answering. Yes, they are Peace lilies!
Kristina
Hi Kristina, now I know what the problem is. Peace lilies are prone to brown edges if they have ever wilted or if they have been over-watered. If they have ever wilted, what happens is, a layer of roots has died back. This means they have less roots–but we’re still watering them on the same schedule so they end up staying too wet. Or if you’re afraid of them wilting and thereby water too much right from the beginning. What you want to do with Peace lilies, is to allow the top two to three inches to dry out (check with your finger) but DO NOT allow the Peace lily to wilt. When you do water, water thoroughly, but do NOT allow to stand in water longer than a few minutes.
This should take care of the problem. If you have questions, you can always bring the Peace lily in here for us to look at.
I have 2 Hydrangea bushes planted at the downspouts as they require more water.
I see the edges of the leaves turning brown.
Is this from too much water or too little water ? I am afraid to put my hand underneath the bush to test the soil.
It’s more than likely too wet. However, you do need to see what’s going on with the crown of the plant. Hopefully you did not pile mulch around the neck–plants don’t like that. How much water is the hydrangea actually getting and does the soil in that area stay damp all the time or does it drain well? Hydrangeas like one inch of water once a week–one good deep watering a week–not a sprinkle every couple of days. You can always bring a sample of a leaf in to us to get a definitive diagnosis.
Bonnie
What is the best time of day to water?
Hi Lois,
When you water in the heat of the day, a lot of it evaporates. Best to water either very early morning or late in the evening. Since I’m by no means a person that’s going to get up at the crack of dawn, I water in the evening. Remember, not to get the foliage wet if you can avoid it.
What is the best way to water hanging planters? I tend to water them in the center, just because it is easy, but have read that the yshould be watered under the leaves on the edges.
When you water a hanging basket, you want to water them thoroughly so that the water runs into the attached saucer. Outside, I just put my hose up and water until water pours out the bottom. In the house, I take mine to the kitchen sink and water so I can water thoroughly
When will you have a Repotting day, Bonnie? I would like to bring my pot of Peace lilies and Bird of Paradise to be put into smaller units. There’s a smaller shoot of BOP that can be separated from pot that has tall mother plant. S I don’t know best way to divide & shorten the older one.
I am retired so it doesn’t have to be a Sat. to bring them in.
Jane, our foliage department can repot any time of the year. Do be prepared to leave your plants for a day or two as we’re pretty busy this time of year. But we’ll take care of them for you.