- 5 Signals You Are Underwatering Plants
- Grow plants without water
- How can humans survive if the world gets drier? Here’s one scientist’s answer … so-called “resurrection” crops.
- How to Care for House Plants
- What biological process causes flowers to wilt?
- Overwatering vs. Underwatering (and how to treat both)
- Signs of Underwatering:
- Why Is Too Much Water Bad For Plants?
- What Causes Overwatering Of Plants?
- Overwatered Potted Plants
- Overwatered Landscapes
- Overwatered Lawns
- How To Water
5 Signals You Are Underwatering Plants
Author: Richard Restuccia November 1, 2016 3 min read
Unfortunately the signals you receive from your plants for under watering are similar to the signals you receive when you overwater plants. Under watering and overwatering plants many times reach the same outcome – sick or dead plants. Below are some important signs to look for that will help you determine if you are overwatering or under watering your plants.
Your Plant is Wilting
Wilting is a sign of both under watering and overwatering your plants. In the case of under watering the plant, when you feel the leaves you will notice they are crisp not limp. Wilting in this case is a symptom of a lack of water passing through the cells of a plant. Plants have pores on the surface of leaves called stoma. They allow air to enter plants. When plants do not have enough water they close their stoma to stop evaporation and this leads to wilting. Remember plants also wilt because of other reasons including overwatering, too much sun, being root bound, too much fertilizer, or some diseases. Unfortunately, plants can’t talk so we can’t just ask them what’s wrong…or can we?
The Soil is Dry
A simple solution for testing soil moisture is a long screw driver. Walk your property and press a screwdriver into the ground. When the soil is moist, the screwdriver should penetrate the soil easily. The depth of penetration will vary by the soil type, size of screwdriver, and your strength. As the soil dries up, the screwdriver will be harder and harder to push into the soil.
A slowdown in growth is a sign a plant is not receiving enough water. This can be a temporary or permanent situation. If the plant experiences a temporary decrease in water supply, the growth may just slow for a short period. If the challenge is more permanent you may see new leaf growth being smaller than normal.
The lower leaves usually suffer first, becoming yellowed and curled. The leaves also can develop dry edges.
Footprints Remain Visible on Turf
Walk across your lawn late in the day and examine the lawn behind you to see if your steps left any “footprints.” Your footprints will appear in a lawn when the grass blades have low levels of water in their tissues. When the grass blades are compressed by your feet, the low water levels prevent the grass blades from springing back up. If your footprints remain for an extended period of time, the lawn should be watered to prevent the grass from becoming dormant or possibly dying.
To determine if you are under watering or overwatering you will probably need to try a combination of activities. For example, when you notice yellow leaves and then check the soil with a screw driver to see if it is moist or dry. Once again we go back to the basic of water management. Understanding the signs of overwatering and under watering are the basics for more sophisticated water management. I’m sure you have a few to add to the list and would love to hear your comments about under watering. If you enjoyed this post please consider subscribing or follow me on twitter @H2oTrends.
Grow plants without water
How can humans survive if the world gets drier? Here’s one scientist’s answer … so-called “resurrection” crops.
Ever since humanity began to farm our own food, we’ve faced an unpredictable frenemy: rain. It comes and goes without much warning, and a field of lush leafy greens one year can crackle, dry up and blow away the next. Food security and fortunes depend on rain, and nowhere more so than in Africa, where 96% of farmland depends on rain instead of the irrigation common in more-developed places. It has consequences: South Africa’s ongoing drought — the worst in three decades — will cost it at least a quarter of its corn crop this year.
Biologist Jill Farrant (TED Talk: How we can make crops survive without water) of the University of Cape Town in South Africa says that nature has plenty of answers for people who want to grow crops in places with unpredictable rainfall. She is hard at work finding a way to take traits from rare wild plants that adapt to extreme desiccation and use them in food crops. As the Earth’s climate changes and rainfall becomes even less predictable in some places, those answers will grow even more valuable. “The type of farming I’m aiming for is literally so that people can survive as it’s going to get more and more dry,” Farrant says.
Extreme conditions produce extremely tough plants. In the rusty red deserts of South Africa, steep-sided rocky mounds called inselbergs rear up from the plains like the bones of the earth. The hills are remnants of an earlier geological era, scraped bare of most soil and exposed to the elements. Yet on these and similar formations in deserts around the world, a few ferocious plants have adapted to endure under ever-changing conditions.
Farrant calls them resurrection plants. During months without water under a harsh sun, they shrivel and contract until they look like a pile of dead gray foliage. But rainfall can revive them in a matter of hours. Her time-lapse videos of the revivals look like someone playing a tape of the plant’s demise in reverse.
The big difference between “drought-tolerant” flora and these tough plants: metabolism. Many different kinds of plants have developed tactics to weather dry spells. Some plants store reserves of water to see them through a drought; others send roots deep down to subsurface water supplies. But once these plants use up their stored reserve or tap out the underground supply, they cease growing and start to die. They may be able to handle a drought of some length, and many people use the term “drought tolerant” to describe such plants, but they never actually stop needing to consume water, so Farrant prefers to call them drought resistant.
Resurrection plants, defined as those capable of recovering from holding less than 0.1 grams of water per gram of dry mass, are different. They lack water-storing structures, and their niche on rock faces prevents them from tapping groundwater, so they have instead developed the ability to change their metabolism. When they detect an extended dry period, they divert their metabolisms, producing sugars and certain stress-associated proteins and other materials in their tissues. As the plant dries, these resources take on first the properties of a honey, then rubber, and finally enter a glass-like state that is “the most stable state that the plant can maintain,” Farrant says. That slows the plant’s metabolism and protects its desiccated tissues. The plants also change shape, shriveling to minimize the surface area through which their remaining water might evaporate. They can recover from months and years without water, depending on the species.
What else can do this dry-out-and-revive trick? Seeds — almost all of them. At the start of her career, Farrant studied “recalcitrant seeds,” such as avocados, coffee and lychee. While tasty, such seeds are delicate — they cannot germinate if they dry out (as you may know if you’ve ever tried to grow a tree from an avocado pit). In the seed world, that makes them rare, because most seeds from flowering plant are quite robust. Most seeds can wait out the dry, unwelcoming seasons until conditions are right and they begin growing. Yet once they start growing, such plants seem not to retain the ability to hit the pause button on metabolism in their stems or leaves. After completing her Ph.D. on seeds, Farrant began investigating whether it might be possible to isolate the properties that make most seeds so resilient and transfer them to other plant tissues. What Farrant and others have found over the past two decades is that there are many genes involved in resurrection plants’ response to desiccation. Many of them are the same that regulate how seeds become desiccation tolerant while still attached their parent plant. Now they are trying to figure out what molecular signaling processes activate those seed-building genes in resurrection plants — and how to replicate them in crops. “Most genes are regulated by a master set of genes,” Farrant says. “We’re looking at gene promoters and what would be their master switch.”
Now, to add those resilient genes to useful crops. Once Farrant and her colleagues feel they have a better sense of which switches to throw, they will have to find the best way to do so in useful crops. “I’m trying three methods of breeding,” Farrant says: conventional, genetic modification and gene editing. She says she is aware that plenty of people do not want to eat genetically modified crops, but she is pushing ahead with every available tool until one works. Farmers and consumers alike can choose whether or not to use whichever version prevails: “I’m giving people an option.” Farrant and others in the resurrection business got together last year to discuss the best species of resurrection plant to use as a lab model. Just like medical researchers use rats to test ideas for human medical treatments, botanists use plants that are relatively easy to grow in a lab or greenhouse setting to test their ideas for related species. Boea hygrometrica, also known as the Queensland rock violet, is one of the best studied resurrection plants so far, with a draft genome published last year by a Chinese team. Also last year, Farrant and colleagues published a detailed molecular study of another candidate, Xerophyta viscosa, a tough-as-nails South African plant with lily-like flowers, and she says that a genome is on the way. One or both of these models will help desiccation researchers test their ideas — so far mostly done in the lab — on test plots.
Understanding the basic science first is key. There are good reasons why crop plants do not use desiccation defenses already. For instance, there’s a high energy cost in switching from a regular metabolism to an almost-no-water metabolism. It will also be necessary to understand what sort of yield farmers might expect and to establish the plant’s safety. “The yield is never going to be high,” Farrant says, so these plants will be targeted not at Iowa farmers trying to squeeze more cash out of already-lush fields, but subsistence farmers who need help to survive a drought like the present one in South Africa. “My vision is for the subsistence farmer,” Farrant says. “I’m targeting crops that are of African value.”
Lucas Laursen is a journalist covering how people use science, markets and serendipity to test new ideas. He has written for Scientific American, IEEE Spectrum, and produced radio for Deutsche Welle (in English) and NPR’s Here and Now.
- climate change
- Jill Farrant
- South Africa
- TED Global
How to Care for House Plants
Plants are living beings and prefer regular care, but frequent or lengthy absences need not stop you from filling your home with greenery. Some house plants, such as cacti and succulents, can literally go for months without water and should be perfect for even frequent travelers. By using watering systems such as wicks, capillary matting, and hydroculture, you can keep most plants happy for two weeks or even more. The plants that need the least care are those grown in sealed terrariums. They can often go for years without water!
Flood house plants with water and place them on
a water-filled tray before leaving on a long trip.
Leaving House Plants at Home
If you suddenly find yourself facing a prolonged absence and your house plants aren’t able to survive on their own, there is no need to panic. There are a few last-minute tricks you can try to keep even difficult house plants living during long periods without regular care.
Start by setting them in a shady spot and removing any flowers and buds to reduce the amount of water they need. Although plants normally don’t like waterlogged soil, they can put up with it occasionally, so set them in a deep tray and literally flood them with water. After this treatment, most plants can go for at least three weeks on their own.
Fragile plants can be covered in plastic when you are away from home for a long time. Since no water is lost to evaporation, plants can go for over a month without care.
Finally, you can simply leave your plants in the care of a horticulturally experienced neighbor. Have your neighbor come in once or twice a week and water as needed.
Want to learn about house plants by type? Try these:
- House Plants
- Full Sun House Plants
- Bright Light House Plants
- Filtered Light House Plants
- Light Shade House Plants
- Hanging Basket House Plants
- Floor Plant House Plants
- Table Plant House Plants
- Terrarium Plant House Plants
- Very Easy House Plants
- Easy House Plants
- Demanding House Plants
- Temporary House Plants
- Flowering House Plants
- Climbing or Trailing House Plants
- House Plants with Colorful Foliage
- Fragrant House Plants
ABOUT THE AUTHOR:
Larry Hodgson is a full time garden writer working out of Quebec City in the heart of French Canada where he grows well over 3,000 species and varieties. His book credits include Making the Most of Shade, The Garden Lovers Guide to Canada, Perennials for Every Purpose, Annuals for Every Purpose, Houseplants for Dummies, and Ortho’s Complete Guide to Houseplants, as well as other titles in English and French. He’s the winner of the Perennial Plant Association’s 2006 Garden Media Award.
Everyone wants gorgeous houseplants. They liven up even the dullest corners of a room, but remembering to, you know, actually care for them can be a hassle. Sure, there’s an app for that, but not all plants are so high maintenance. In fact, some are happier if you leave them alone and water them less often. These are those plants.
1.String of Pearls
Anita MarksGetty Images
If you have the tendency to forget about your little green friends for way longer than you’d like to admit, these bead-like plants should be an immediate yes. Originating from South Africa, they not only can tolerate a dry environment, they also require very minimal water. Plus, if you’re lucky enough to get it blooming, you’ll notice their white flowers smell just like cinnamon.
BUY NOW String of Pearls, $5; Amazon
GETTY IMAGES CHRIS LESCHINSKY
It’s no secret that succulents, the little trendy plants, have taken over Instagram. They have gorgeous geometric shapes, hues and they’re easy enough to take care of as they have secret water reservoirs up their leaves. Dousing them weekly is usually sufficient but be sure to check that their soil is dry before watering again.
BUY NOW Succulents (five-pack), $16; Amazon
3. Ponytail Palm
This Southeastern Mexican beauty gets its name from skinny leaves coming from a thick stalk shape. Find a sunnier spot for it in your home to show it off, and as for watering, keep the soil dry. Yes, you read that right—the Ponytail Palm likes to be watered every few weeks.
BUY NOW Ponytail Palm, $43; Amazon
4. ZZ Plant
These tall, slender beauties have rubbery leaves and are pretty indestructible. If you have the choice, they prefer moderate levels of sunlight. “These plants prefer to stay on the dry side, and seem to thrive on neglect,” says Kathie Hayden, plant information service manager at Chicago Botanic Garden.
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Little White Whale
Perfect for first-time plant parents, the Pothos plant is undemanding. They’re fine with low light, too, so bathrooms or offices are no problem for them.
BUY NOW Pothos, $9.50; Amazon
6. Snake Plants
This one’s definitely for the forgetful type, given that you can go weeks without watering it. Word on the street is that it can improves indoor air quality in your home, too.
BUY NOW Snake Plant, $29; Amazon
7. Air Plants
Air plants can grow literally anywhere—no soil needed. We love them propped up on a shelf, or hanging mid-air. To water, dunk them every 10 days and let them dry out after in a sunny spot.
BUY NOW Air Plants In Crystal Planters (set of three), $19; Amazon
the begonia brigade
Begonias are known for their big, gorgeous leaves making a bold contrast in any room. They’re definitely easy to care for, but they can be sensitive to overwatering, so simply wait until the leaves droop before watering again.
BUY NOW Begonia Seeds, $6.50; Amazon
9. Zebra Cactus
VALERIA VECHTEROVA/GETTY IMAGES
Zebra Cacti are some seriously exotic-looking houseplants that will rack up major compliments from whoever visits your home. They may not like cold or drafty areas, but they’re still very low maintenance, needing water only once a month.
BUY NOW Zebra Cactus, $14.48; Amazon
DEA / C. DANIGetty Images
These tropical beauties with origins in Madagascar, are full of character and durability. Dracaenas are a no-brainer for accidental plant killers, as they’re tolerant to extreme indoor conditions and can survive even when well under-watered!
BUY NOW Dracaena, $11.58; amazon.com
11. Pregnant Onion
Getty Images Kindra Clineff
The name of this curvy bulb is unforgettable, but it’s a pretty apt moniker: The plant makes babies. So many little bulblet babies! If you’re ready to raise one, all you have to know is that you can let the soil totally dry out between waterings. Yes, really.
BUY NOW Pregnant Onion, $9.99; amazon.com
A few days ago we noticed that one of our little pumpkin plants on the window sill had wilted. The soil looked dry so we watered the plant and after a few hours it was standing lovely and straight again, which got us wondering why do plants need water.
Plants need water to germinate.
We saw this with our bean in a jar. Water is needed to activate the process of germination, it also softens the seed making it easier for the plant to break through.
Photosynthesis is the process by which plants make energy to grow. Photosynthesis requires sunlight, water and carbon dioxide. We demonstrated what happens when a plant cannot photosynthesise when we made our cress caterpillar.
Plants need water to absorb nutrients from the soil.
Transpiration is the process by which water moves up the stem of a plant from root to leaf when water is lost from the plant due to evaporation occurring at the leaves. This continual flow of water and nutrients keeps the plant’s cells firm, if the cells become short of water they lose firmness and the plant starts to wilt.
We can demonstrate transpiration by placing white flowers in coloured water, the water travels up the stem to the petals which become coloured like the water.
Have you ever noticed your plants wilting? Did they revive after you watered them?
Suitable for Key Stage 1 – Living things and their habitats
What biological process causes flowers to wilt?
Sarah – Well there are two different things that are going on here. There’s the argument of why plants wilt, so in the case if you have a house plant, and why if you don’t water it, it wilts. I’ll address that first.
Usually in plants, the cells within the plant are what are known as turgid, which means that they’re absolutely stuffed full of water which keeps moving into them by osmosis. They’re very rigid which is how plants are able to support themselves. But if they’re not able to get enough water, water will move out of the cells and the cells become sort of floppy or what’s known as flaccid and that is why the plant is no longer able to support itself and the leaves go all floppy and wilted and soft. So that’s what happens if you don’t get enough water, but there are actually some other reasons behind cut flowers wilting. So obviously, if you don’t water them, the same thing will happen, but also, it can be because they run out of nutrients because obviously, they’re no longer attached to roots that are getting any nutrients as well and there can be a build up of bacteria, and fungi, and things on the end of the cut surface.
But also, when you cut flowers, you cut them on your work top or whatever and then you put them in water. Because of the water tension within the xylem vessels (which are the vessels that go up and down a plant, carrying the water around), if you cut the stem, it sucks in a bubble of air into the xylem. If you then put the stem in water, it stops more water from flowing up the xylem. So that actually can be a real reason why they wilt. Some florists recommend that you cut the stems of flowers underwater which will keep the water just a little droplet on the end whilst you put them in the vase and will help them to stay alive for longer.
Overwatering vs. Underwatering (and how to treat both)
Signs of Underwatering:
Drooping leaves that look completely lifeless can be a sign of underwatering.
Soil pulling away from the outsides of the pot is another indicator that your plant may be underwatered. If you notice this happening, try shortening the length of time between waterings.
Drying out too quickly could mean that your plant may need to be repotted. If your plants’ pot is too small to support the amount of water it needs to thrive, this can inhibit future growth and be detrimental to your plant in the long run. Consider repotting your plant after the first year of ownership.
To keep things simple, water your plant the same amount each week – about 2 cups for plants 2-3ft tall and 3 cups for plants 3-6ft tall.
Keep plants happy and healthy by observing and listening to what it is they’re trying to tell you. And remember, the amount of water your plants need will change depending on the season and the conditions in their environment.
Need additional help caring for your greens? Exclusive for Léon & George customers, our plant doctors are available 24/7 for any questions about keeping your plants happy and healthy! Email us anytime at [email protected]
Problem: If your plant is drooping, then it’s usually a sign of either over or under-watering.
Cannabis Underwatering Symptoms
- drooping (plants often get better after being watered)
- leaves often seem “papery” and thin because they don’t have any water inside them. (This is opposed to overwatering where the leaves often feel bloated and “fat” from all the water contained inside)
- chronic underwatering eventually leads to yellowing leaves and nutrient deficiencies
If your soil or soilless medium looks bone dry every time you water, or if you know that your roots have dried out, than skip right down the the solution section, as you definitely have a case of underwatering.
Under-Watered Cannabis Seedlings – Leaves feel papery and thin, growing medium is dry
If it gets worse….
The marijuana plant in the middle is under-watered, causing it to droop. Because it was taller and directly under the grow light, it became underwatered even though it was getting the same amount of water as its siblings. Sometimes you’ll see signs of under-watering immediately after upgrading your grow lights (if you don’t change your watering habits), because all the plants start drinking more due to the extra light and heat.
Chronic Under-Watering (Under-Watering on a Regular Basis)
Most growers tend to give too much – not too little – water to their plants. However, if you’re spending long periods away from your marijuana plants or the containers are drying up in less than a day or two, it may mean that your plant needs to be watered more often, or be given more water at a time.
It’s also common to under-water when plants start overgrowing their pots, or if growers get on a schedule of giving a specific amount of water as opposed to paying attention to the soil.
- plant may need to be watered more often
- plant may need more water at a time
- plant may have overgrown its pot and need to be transplanted
It can be difficult to diagnose chronic underwatering because problems may look like nutrient deficiencies. One big clue is that plants perk up every time after you water.
Chronically Under Watered Seedlings – These yellow leaves are actually caused by the plants being slightly under-watered on a regular basis
The curling/clawing and burnt tips on the following two plants may look like it could be caused by another problem, but in this case the symptoms are the result of the plant being regularly under-watered
Notice how the leaves are clawing and tips appear burnt alomost like nutrient burn. It’s happening because the plant isn’t getting enough water on a regular basis.
The leaves near the buds of this male cannabis plant started turning yellow. In this case, the grower determined it was because the plant had overgrown its pot and was drinking more than expected, and as a result the soil was getting too dry between waterings.
More examples of under-watered cannabis plants
Extreme underwatering on a big plant
Not Sure? If you’re not sure whether your plant needs more or less water, how do you figure out exactly why your plant is drooping?
1.) Determine: Is my plant over-watered?
A cannabis plant does not get over-watered because it’s given too much water at once – overwatering is caused by the plant being watered too often, or if the plant does not have proper drainage (which means the growing medium is taking too long to dry out).
2.) If not over-watered, does my plant have root problems?
Growing hydroponically? When you see signs of wilting and overwatering in a plant that is growing hydroponically with the roots in water, usually that’s a sign of a root problem like root rot.
In fact, all cannabis plants can sometimes display wilting/drooping symptoms that are actually the result of root problems.
3.) You may be seeing symptoms of under-watering
So if you read the short description in step 1 about what causes overwatering (and you’re sure you haven’t overwatered your cannabis plants), and you’re certain you’re not seeing signs of root problems, than your cannabis plant might be drooping or wilting because it needs more water.
If you’ve been underwatering your plant, its leaves will look limp and lifeless, like these plants.
Symptoms of underwatering look the same whether your cannabis plant is growing in soil or a soilless growing medium like coco coir or perlite.
How can I tell if my cannabis plant is over or under-watered?
Does my plant actually have root problems?
Don’t wait until leaves droop to water your potted cannabis plant! While it is generally a good idea to let your potted cannabis plant dry out a bit after watering (watering too often causes its own problems), you should always water your cannabis plants again before the leaves start drooping.
This is the case for cannabis plants grown in both soilless growing mediums and soil.
First-time growers tend to overwater their plants, but underwatering happens too.
So you’re pretty sure your plant is under-watered. A thirsty cannabis plant will usually perk up quickly after the roots are given water.
1 picture taken every 75 minutes. Strain is Island Sweet Skunk. Used with permission. By micks_trichs.
Watch another time-lapse – middle plant is very under-watered and perks up after getting water
6 plants, 1 photo per minute for 125 minutes. Used with permission. By micks_trichs.
Learn about ones of the best ways to properly water your potted cannabis plant every time…
How to water cannabis properly (for soil and most soilless mediums)
Wait Until Plant Needs Water – Wait until the top of the growing medium is dry about a half inch deep (up to your first knuckle). Preventing the topsoil from staying wet for long periods of time can also help prevent bugs like fungus gnats. Some growers prefer the “lift the pot” method to figure out when plants want water, where they actually lift the plant to see if it feels light from lack of water. Some non-soil growers, especially in coco or a very high-drainage growing medium, may water a little earlier when the top is just starting to dry out because it’s more difficult to overwater plants in that type of environment. If you continue running into problems with underwatering, you might consider watering more often than is generally recommended. It may be you need extra watering due to small pot size, rootbound plants, temperature, humidity, etc.
Water until you get a little runoff. If using nutrients in the water, add water until you see 10-20% extra runoff water drain out the bottom of your pot. This helps prevent nutrient buildup in the soil and if you have good drainage this type of watering schedule causes plants to grow faster than if you don’t water to runoff (it also makes it much harder to under-water your plants). If not using added nutrients (plants getting all nutrients from the soil, for example in a super soil setup), then only water until you get just a tiny bit of runoff out the bottom, so you’re not washing out your nutrients. However, you still want to make sure you’re saturating your medium – you don’t want dry spots in the soil!
Go back to step 1. If water does not come out quickly or pots take more than 5 days to dry out for step 1, you may have a drainage problem or need to give less water at a time until your plant is drinking more. If pots are drying out in just 1-2 days, you may need to give more water at a time, or transplant to a bigger pot.
Learn more about how to water your cannabis plants perfectly every time
A simple way to tell if a potted plant is ready to be watered is to pick it up and tell if it feels heavy or not.
As plants use up all the water in their pot, it will get lighter. If you need something for comparison, you can get an extra pot and fill it with your growing medium. Now you can use this extra container for comparison with your potted plants as it represents the ‘dry weight’ of your growing medium. If you pick up a potted plant and its feels just slightly heavier than your dry pot, then you know it’s time to water your plant. After a while you get a feel for how heavy your plants need to be and you may not even need the extra pot anymore.
Need more help?
If your plant is experiencing “the claw” and not just normal drooping (the ends of leaves are curling like a claw or pointing down like talons), then you may actually have a nitrogen toxicity (too much nitrogen).
These Plants Are NOT Over or Underwaterd, These Leaves Show Signs of
(“The Claw”, tips bent down, curling / clawing, dark green leaves)
When people find out I have horticulture experience, they generally respond with, “I kill all my plants.” After hundreds of these interactions, I’ve discovered the number-one reason people believe they have a black thumb: Overwatering.
What are the signs of overwatering plants? The signs of overwatering plants are almost identical to underwatering. Both cause wilting and dead or dying leaves. Overwatering is most common in potted plants, but it can also affect landscapes and lawns. The only way to diagnose overwatering is to check the soil.
There are multiple factors that can exacerbate the problem, so it’s important to take a holistic approach to identifying and solving an overwatering issue.
Why Is Too Much Water Bad For Plants?
Healthy soil has a 1:1 ratio of water to air. The symptoms of overwatering are actually symptoms of a plant suffocating because they can’t breathe.
Plants need oxygen and water for transpiration and photosynthesis. These processes create byproducts that must be expelled through pores in the leaves. As leaves expel excess water vapor and gasses, it creates a negative pressure in the plant’s circulatory system. This vacuum is what causes roots to pull new air and water from the soil.
If the soil is waterlogged, then the roots can’t pull up oxygen. Photosynthesis and transpiration will slow down, and eventually stop if the water is unable to drain from the soil. The roots will rot from anaerobic conditions. The plant will be unable to create energy, growth will stop, and the plant will die.
What Causes Overwatering Of Plants?
The obvious answer is too much water. However, there are two other reasons a plant will suffer from large amounts of water:
- The plant is in the wrong place
- The soil is compacted clay
Plants have specific requirements for sunlight, nutrition, and water. A cactus will quickly suffer from overwatering in a rainforest, while the ferns and vines thrive.
If drought-tolerant plants are watered too often, they will show signs of overwatering, even in healthy soil. It’s important to become familiar with your lawn and landscape so you’re aware of the water requirements of each plant.
Soil structure is the more common cause of overwatering. Even with a good irrigation schedule, compacted, clay soil will hold too much water.
Clay soil textures are composed of fine particles. These particles pack tightly together and create small pore spaces. This porosity makes it hard for the soil to absorb water, but once it is saturated, it is incredibly difficult for water to drain.
Plants will respond to poor drainage by growing surface-level roots in an attempt to absorb oxygen. This is especially apparent in lawns.
Lawns grown in clay soil will respond to overwatering by growing a dense matt of shallow roots. When the soil is saturated, the grass will be green. However, as soon as the water drains below the first few inches of topsoil, the roots will be too shallow to access it. The grass will quickly suffer from a lack of water, and most homeowners decide to irrigate in response.
This creates a cycle of shallow roots that experience extremes of moist and dry soil conditions. Potted plants and landscapes can experience the same cycle if they do not have proper drainage.
Overwatered Potted Plants
When potted plants die, it is almost always due to overwatering.
Common signs of an overwatered potted plant are:
- Wilting when the soil is wet
- Pale green or yellow foliage
- Leaf drop
- Rot near the base of the plant
- Foul smell near the base of the plant
If you have been watering a plant consistently, but it never perks up, pull it out of the pot. Roots should be white and firm. If they are yellow and mushy, the roots have rotted from overwatering.
Wash the pot thoroughly with a mild bleach solution, and allow it to dry. Remove as much of the old, saturated soil as possible without damaging the roots. Pull out dead or dying roots and discard with the old soil.
Make sure the pot has 3-5 drainage holes, and add some pebbles and rocks to the bottom for drainage. Have someone hold the plant in the pot while you add soil. The roots should start about 1” below the top edge of the pot. Gently tamp the plant into the soil, and place the pot up on a surface where it can drain freely. Water thoroughly, and place in indirect sunlight.
When landscapes are overwatered, it’s usually due to poor drainage and poor placement.
Common signs of overwatered landscapes are:
- Wilting when the soil is wet
- Pale green or yellow foliage
- Soft, droopy leaves
- Leaf drop
If only one or two plants are overwatered, while the rest look healthy, it is likely because the plant is in the wrong location.
Plants that have needles, grey foliage, and hairy foliage tend to like dry conditions. Asters and succulents are also sensitive to overwatering.
Try replacing the affected plants with something that tolerates more water. You can also replant the affected plants near the edges of your landscape beds. This will give them the most sunlight, and keep them away from leaky gutters.
If the whole landscape looks overwatered, the problem is the soil.
The first step is to examine the soil. Pull back the mulch and remove any weed barriers.
If your landscape bed has a black plastic weed barrier, water will have a hard time evaporating, and it will be very difficult for organic matter and oxygen to enter the soil. Removing this black plastic will help the soil regulate water levels more efficiently.
If your soil is compacted, wet, and holds shape like modeling clay, you need to add organic matter. Allow the soil to dry out until it is moist but you can’t squeeze any water from it.
Next, break up the top layer of soil as much as possible without damaging established plants. Add a ½” layer of compost across the entire landscape bed, and gently rake it in.
Spread a 3” layer of hardwood mulch on top to help regulate moisture and help prevent weeds. Avoid walking on your landscape bed as much as possible, because this will compact the soil and cause drainage problems.
You may also want to check for leaky gutters and drain pipes that could be causing an excessive amount of water in your landscape bed. Ensure all rainwater is drained away from the house, and that you only plant water-loving plants in those areas.
Lawns are a naturally high-traffic area, and become compacted easily.
Common signs of overwatering a lawn are:
- Pale green or yellow blades
- Excessive weed growth (weeds grow faster than grass)
- Shallow roots
- Insect damage
- Mushrooms and ring spots (source)
- Spongy feel
While it’s possible that you have the wrong grass for your climate, it is much more likely that an overwatered lawn is due to soil issues and watering too frequently.
For lawns, it’s important to encourage deep root growth. This helps them develop some drought resistance, and enables them to handle stressful weather conditions.
With compacted soil, roots grow shallow. So, to help overwatered lawns, start aerating once or twice per year, and topdressing with ½” of compost. This will incorporate oxygen into the soil, break up compaction, and add in organic matter.
How To Water
Once you’ve diagnosed an overwatering issue, and solved any underlying placement and soil issues, it’s time to set up a healthy watering schedule. As a general rule, it is better for a plant to get too dry than too wet.
Allow the top 1/4 of potting soil to dry out before watering potted plants.
Place the pot in a sink or on a well-drained surface. Water thoroughly, and wait until the water has finished running out the bottom before replacing into decorative pots or stands.
Irrigation needs for landscapes will change depending on the season, type of landscape, and age of the plants.
Established shrubs and trees may not need any supplemental water. Landscapes with annuals will need significantly more water than native perennials.
As a general rule, water once per week for a few hours. Pull back the mulch around plants and check the soil before watering in the spring and fall to avoid overwatering. Soil should be dry in the top inch before watering.
The golden rule of lawn irrigation is deep and infrequent.
Grass roots grow towards water, and for healthy lawns, we want roots to grow as deep as possible.
To encourage this, water deeply, about 1”-1.5”, once per week, early in the morning. Allow the grass to show signs of water stress before watering again.
This will force roots to grow down towards water held in the subsoil, as opposed to light, frequent watering, which enables roots to thrive in the top 2” of soil.
After a few months of deep, infrequent watering, lawns build up a tolerance to drier conditions, and are able to utilize water more efficiently.
Overwatering is the most common cause of plant death. It’s also easy to avoid if you know what signs to look for.
The #1 sign of overwatering is wilting in wet soil.
Fortunately, most plants can be rescued as long as you catch it early. Allow plants to wilt some before watering, and install plants with similar water needs in your landscape.
For information on building a drip irrigation system or common DIY irrigation myths, please visit our irrigation articles.
How can I make my landscape more water-efficient?
The best landscapes are full of native plants. Native landscapes are already adapted to the average rainfall in your area, and they will require only occasional supplemental water. Contact your local extension agency for information on native plant nurseries.
Should I use sprinklers, hoses, or drip irrigation?
This will depend on what you are watering. Sprinklers are the only practical way to water lawns, but they lose a lot of water to evaporation. To avoid this, water early in the morning.
Landscape plants may burn or mold if the foliage is frequently damp from watering, so it’s better to install drip irrigation under a layer of mulch. You can also control how much water each plant gets.
Hoses are a good way to water small areas or individual plants. For trees and shrubs, leave a hose trickling near the base of the trunk for a few hours whenever watering is required. For small gardens, watering by hand in the morning is better than attaching a sprinkler to a hose, because you can direct water to where it’s needed.