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Root rot is a sneaky way for plants in the garden or in pots to die, as it breaks down the roots below the surface. What you see happening to the plant on top, though, usually looks like you’ve just given it too much water or the plant isn’t getting enough food. Most of the time by the time gardeners figure out a plant has root rot, it’s already quite bad and there isn’t much time left to save it. Experts in plant diseases say root rot is one of the three most common reasons garden plants die, and it’s the number one reason for plants in containers to die, and this is often because of drainage issues and too much watering.

“Root rot” is how we describe the problem, not a specific illness. Many fungi that live in the soil, like Phytophthora, Pythium, Fusarium and Rhizoctonia, are responsible for root rot when the soil is soaking wet. These fungi are in almost all garden soil in small quantities, and when the soil drains well and the roots can get air, they’re more or less asleep and won’t do anything. But, if the soil is full of water and the roots are cut off from oxygen, the fungi become active, start to damage roots that aren’t strong, and can destroy all the roots in from a few days to a couple of weeks, depending on things like the temperature.

Recognizing Root Rot Before It Becomes Fatal

When root rot first shows itself, the plant will start to droop as if it needs water, even though the soil is wet, the lower leaves will turn yellow, and it will generally look unwell. Watering or giving it plant food won’t help. These symptoms are very similar to what happens when you water a plant too much – and in fact, overwatering is the main reason for root rot, so the two are strongly connected. The best way to be sure what’s going on is to look at the roots. Healthy roots are white or a creamy colour, are solid when you gently squeeze them, and smell of fresh earth. Roots with rot will be brown or black, soft and breaking down in your hands or be slimy, and can have a bad, rotting smell. With plants in pots, you can easily pull the entire root system out of the container for a quick look. If it’s a plant in the ground, carefully dig around the base of the stem to expose the upper roots so you can see what they are like.

 

Treating Root Rot in Container Plants

If your potted plant has root rot that isn’t too far along (so you can still see some good white roots amongst the bad), you can often save it, but you need to act quickly. Take the plant out of its pot and carefully rinse all the old soil off the roots with water. With clean, sharp scissors or pruning shears, get rid of any roots that are brown, mushy, or slimy and disinfect your tools with rubbing alcohol between each snip. Also, get rid of roots that fall apart at a touch, because they’re dead and won’t get better. You should be left with only firm, white, healthy roots, and you might have to remove over half of the roots to achieve this.

Use a clean pot (or the original, after being really well cleaned with a weak bleach solution) and fresh, sterile potting mix that drains well to repot. The new pot absolutely needs drainage holes. After repotting, don’t water much, just enough to get the soil to settle, and put the plant in a bright spot that doesn’t get direct sun while the smaller root system gets going. And for at least six weeks, don’t use any fertilizer; damaged roots are easily burned by it. With enough healthy root left, the plant should improve in two to six weeks.

Managing Root Rot in the Ground

Root rot in the ground is trickier to handle because you can’t just swap out the bad dirt. If the plant is small enough to get out of the ground, you can cut away the rotten roots and replant it, but this time in a heap of good, enriched earth that’s higher than the soil around it. This helps the roots to drain better as they recover. For bigger plants, bushes and trees that are too large to dig up, the main thing to do is fix what caused the rot in the first place: get water flowing away from the roots, water less, and make the soil around it better by mixing in lots of things from plants and so on. Badly damaged plants in the ground might not make it if too many of the roots are already ruined by the time you realize what’s happening.

 

Prevention: The Most Effective Treatment

It’s a lot easier to stop roots from rotting in the first place than to try to fix them when they do. And the most important thing you can do to prevent root rot is to make sure water drains well wherever you’re growing things. For plants in containers, use pots with lots of drainage holes, a potting mix that drains easily, and don’t let water collect in the tray under the pot for more than half an hour after you’ve watered. Outside in a garden, slope the land so water flows away from your plants, and if you have heavy clay soil, dig in compost and other organic materials to help drainage. Using raised beds solves most drainage problems in the ground as they lift the roots above the level of groundwater. Most importantly, to prevent root rot, water when the soil actually needs it (as you’d find out by testing the soil), not on a set day…this will allow the soil to dry out so roots can get the air they need to be healthy.

Key Takeaway

When the ground stays too wet, fungi that are already in the soil start to work and destroy the roots because they’re cut off from oxygen. You can tell if a plant has root rot by the roots being brown, soft and smelly (good roots are white and firm). Often you can rescue plants in pots by getting rid of all the rotten roots, putting the plant in new soil that drains well, and watering it less. In fact, it’s a lot better to stop rot from starting by ensuring good drainage, only watering when the soil needs it, and using a soil mix that water can easily flow through, than to try and fix it once it’s already happened.

When you move little plants started inside onto the outside to a garden, they go through their toughest time. They’ve been used to lights indoors, a steady temperature, and being shielded from wind, rain and big changes in how hot or cold it is, but all of a sudden they have to deal with everything the weather throws at them. This change actually kills a lot more plants than most people who garden realize. People at the agricultural extension service think 20 to 40 percent of all the vegetables you don’t get in a home garden are because of plants dying when moved, and the reason for this is that everyone does the same things incorrectly when transplanting, and almost nobody ever thinks about whether those things are even wrong.

1. Skipping the Hardening Off Process

The most important thing you can do for seedlings when you’re getting them ready to go outside, and something people very often don’t do completely or even at all, is hardening them off. This means slowly getting them used to life outdoors over a period of seven to fourteen days. Plants started inside have very delicate cell walls, flimsy stems, and a thin waxy coating on the leaves for defense against the sun and wind. If you just put these fragile plants directly into a full day of sun and wind, they’ll get sunburned, dried out by the wind, and dehydrated, all within a few hours! To harden them off, you’ll put your seedlings outside for longer and longer times each day. You’d begin with two hours in a protected, shady spot, and over one to two weeks, increase this until they can be out all day. As they experience being outside slowly, they’ll actually change in structure: cell walls get thicker, stems become stronger, and that waxy leaf coating gets heavier, so they’re ready to live as transplanted plants.

 

2. Transplanting at the Wrong Time of Day

If you move young plants when the sun is at its strongest in the middle of the day, they get the most intense sun and lose a lot of water just when their roots (which have been messed up by the move) are at their worst for taking up any water. It’s much better to transplant in the late afternoon or early evening; the plant then has all the cool of the night to get over being uprooted and start growing into the new earth before it has to deal with the sun and heat of the next day. And transplanting on a cloudy day is even easier on the seedlings, because the weaker sunlight means they will be less stressed, no matter when you do it.

3. Not Watering Deeply Enough at Transplanting

Just a little splash of water when you’ve put a new plant in the ground only gets the very top of the dirt wet. The original root-ball stays encircled by dry soil which then sucks the moisture from the roots. What you should do instead is water very well: completely soak the hole in the ground before you place the small plant in, and then water generously after gently patting the soil by the stem. This makes sure the earth around it is wet down at least six inches deep. This way, there’s no air trapped around the roots and they are immediately in moist soil.

4. Planting Too Deep or Too Shallow

When you’re putting out young vegetable plants, put them in the ground at the very same height they were in their pots; the point where the stem and soil meet should be at the same level as the ground. If you plant them too far down, you’ll get the stem surrounded by wet soil which leads to rot. But if they are too high, the upper part of the roots will dry out quickly in the air. Tomatoes are different though – they like being planted deeply. They will grow new roots all along any stem part that’s underground and this makes for a much bigger, healthier root system.

5. Fertilizing Immediately After Transplanting

Lots of people put fertilizer in the hole when they plant, or sprinkle it around the roots of a plant after they’ve moved it, but this often does more harm than help. Because you’ve broken or damaged the roots while transplanting, they are very easily burned by a lot of fertilizer. A newly transplanted seedling shouldn’t have any fertilizer for at least a couple of weeks, and many experts who work with plant advice say to wait three or four weeks. That gives the roots a chance to recover and start growing into the soil around them before they have to deal with fertilizer.

 

6. Ignoring Wind Exposure

People often don’t realize how much wind stresses little plants that have just been put in the ground. Even a fairly gentle breeze makes plants lose water through their leaves much faster, and at this point their roots aren’t yet good at getting water from the soil they’re now in. If you shield them from the wind for the first week after planting, you’ll save a lot of them, especially if your garden is open to the elements. You can do this with a floating row cover, a quick barrier made of stakes and burlap, or even five-gallon buckets turned upside down (though take the buckets away during the day).

7. Crowding Seedlings Too Close Together

It’s easy to see why you might want to squeeze your young plants a little closer together when you’re setting them out in the garden to get the biggest harvest possible. However, doing that actually works against you. As soon as they’re in the ground, plants packed too tightly start battling each other for water, for food in the soil, for sunlight, and for air to breathe. This struggle makes them get going more slowly, gives you less of a harvest from each plant, makes illnesses more common, and results in smaller, not very good looking fruit. If you stick to the amount of space suggested on the seed packet or the plant label, each plant will have what it needs to grow as much and as well as it can.

Key Takeaway

You can easily prevent the seven things people most often do wrong when transplanting plants: not getting seedlings used to outdoor conditions, doing it in the hottest part of the day, barely getting the roots wet, planting them too high or too low, feeding them right away, not thinking about the wind, and putting them too close together. Give seedlings a week to two weeks to slowly adjust to being outside, transplant in the late afternoon or evening, water really well so the whole root area is moistened, put plants in the ground at the right level, don’t fertilize for two or three weeks, shield them from wind for a bit, and give each plant the amount of space it needs to grow. Doing these things will give you a much, much better chance of your new plants living.

Nearly all of us who grow vegetables have been a bit alarmed to see our plants fall over during the hottest part of a summer afternoon. Their leaves get floppy, the stems bend, and the whole thing looks desperately thirsty. You’d think to grab the hose right away, wouldn’t you? But people who study how plants work suggest you shouldn’t rush. That drooping in the afternoon is one of the things most often misunderstood by home gardeners, and watering every plant that looks like this (which is what you’d likely do) very frequently causes overwatering. This causes much bigger problems than the quick droop you were trying to fix.

Knowing if the drooping is just a short-term thing because of heat, or if the plant is really dry, will help you do what’s right. You can safely do nothing about the harmless kind, but you’ll want to deal with a real lack of water before your plants are harmed permanently.

Temporary Wilt: A Normal Plant Response to Afternoon Heat

Lots of garden plants get rid of water through their leaves (this is called transpiration) more quickly than their roots can pull up new water from the ground on hot afternoons, especially when it’s over 85 degrees and the air isn’t humid. This causes a short-term shortage of water inside the plant, and the leaves and tender stems lose their firmness and start to sag. Importantly, this is not permanent; if there’s enough moisture in the soil, the plant will perk right back up by evening or the next morning, because it won’t be losing water as quickly and the roots will have supplied enough. This kind of wilting is what plants naturally do, and doesn’t mean you haven’t watered them enough.

Plants with big leaves are especially likely to have this temporary afternoon slump as their large surface area loses water quickly. Squash, cucumbers, melons, beans are the vegetables most often affected, and gardeners are often worried into giving them water when they really don’t need it because of how much they suddenly droop in the middle of the afternoon.

 

The Morning Check: The Reliable Diagnostic

To tell the difference between plants just drooping a bit for a short time and actually being really thirsty from drought, the best thing to do is look at them first thing in the morning. Go to your garden before the sun gets strong and look at the plants. If they’ve bounced back completely overnight and look firm and standing up nicely, then they were only a little droopy yesterday afternoon and have enough water in the soil. You don’t need to water them. However, if they still look droopy when it’s cool in the morning, the soil is truly too dry and the roots aren’t getting enough water to them even when the plants aren’t asking for much. If this morning droop is happening, water them a lot and get it down deep, right away

True Drought Stress: Symptoms That Demand Action

If you understand what to pay attention to, you can tell the difference between a plant being truly in drought and just drooping for a bit in the afternoon. The easiest thing to notice is when the drooping doesn’t go away by morning. Also look for edges of leaves curling in, becoming dry and brown; a normal afternoon droop won’t make them turn brown. The older leaves will become yellow and fall off, as the plant sends water to the newer parts. And you’ll find that your fruit is smaller than it should be, or if you have cucumbers, they’ll taste bitter. When drought is really bad, flowers will fall off before any fruit form, and what fruit is there can split or get sunburnt because the leaves that used to provide shade aren’t doing their job.

Why Overwatering in Response to Afternoon Wilt Causes Problems

If the soil is already wet enough, but you water because your plants looked droopy at two in the afternoon, you’ll end up with water filling all the spaces around the roots, pushing out the oxygen. This creates a soggy situation where root rot and fungal diseases can flourish, and unbelievably, causes even more wilting because the damaged roots aren’t able to soak up any water. Many home vegetable gardens are ruined by this repeating problem: the plant wilts, you water it, the ground stays too wet, the roots rot, the plant gets even more wilted, then you water it again. To stop this, you need to believe what you see when you check the plants in the morning, not how they look after the hottest part of the day.

 

How to Reduce Afternoon Wilting Without Overwatering

You can lessen how badly plants droop in the afternoon (and it won’t require a lot of extra water). A nice, thick layer of mulch, three to four inches of straw or shredded leaves for example, will keep the soil much cooler and help the moisture around the roots stay at a pretty consistent level. Shielding plants from the strong afternoon sun with shade cloth, by planting them near something taller, or by putting them on the side of a fence or building that stops the western sun, lowers the heat and bright light which makes plants lose water quickly. And if you use drip irrigation at a set time each morning, the roots get the water when they’re best at soaking it up, and you’ll not get the soggy soil at night that causes fungal diseases.

Key Takeaway

When it’s hot, plants often droop by afternoon, but this is typically just them being temporarily affected by the heat, and doesn’t mean they require a drink. To find out if they really need water is easy: look at your plants first thing in the morning. If they’ve perked up, the soil has enough water and you can leave them be. However, if they are still drooping in the morning, the soil is actually too dry and they need a good, thorough soaking. Applying mulch, watering at the start of the day, and providing some shade in the afternoon can lessen this temporary droop without the danger of overwatering. Overwatering leads to root rot and then much worse drooping, and this begins a ruinous cycle.

Growing peppers at home is very satisfying; however, they’re also pretty fussy about their surroundings and even little changes in how you look after them can hugely affect how many peppers you get. A single pepper plant that’s cared for properly will give you between 50 and 100 smaller peppers throughout the season, or 15 to 25 of the larger bell pepper type. Lots of gardeners don’t achieve these amounts because of some common things they do that accidentally stop the plants from making fruit. Experts from agricultural colleges have figured out what makes a successful pepper plant versus one that doesn’t do so well, and the solutions mostly involve doing things a little differently in your gardening, not spending more money.

Start With Warm Soil — Peppers Will Not Tolerate Cold

Peppers originally come from the warmer regions of Central and South America and they really stop growing, lose their blossoms and won’t produce any peppers if the ground or air gets too cold. Lots of gardeners who are keen to get things planted right after the last frost mistakenly put pepper plants into soil under 65°F. This causes the pepper to be stuck being stressed and unable to grow for three or four weeks. For the pepper to start growing and making peppers right away, the soil at about four inches down should be 70°F and the temperature at night should reliably be over 55°F. If you live somewhere with a cool spring, warming the soil with black plastic sheeting for a fortnight before planting will speed things up.

 

Pinch Early Flowers to Build a Stronger Plant

It seems strange, but getting a lot more peppers from your plants is often done by taking off the very first flower buds that show up on a newly planted pepper. This is known as ‘pinching’. By doing this, the plant puts the energy it would have used to make those first fruits into growing a bigger, stronger root system, a thicker main stem, and a bushier spread of branches. Because the plant is bigger and stronger overall, it can hold many more peppers growing at the same time later on in the season, and this will give you far more than those first few would have. Experts at agricultural colleges and universities advise taking off all flowers until the plant is twelve to fifteen inches tall; at this stage it’s developed enough support for a large crop of fruit.

Feed Correctly at Each Growth Stage

When peppers are growing their stems and leaves, which is for about four to six weeks after you put the plants in the ground, they do best with a fertilizer where the nutrients are fairly equal, but with a middle amount of nitrogen. But as soon as the plant starts to get flowers, you should change to a fertilizer with a lower first number and higher second and third numbers in the NPK listing. This encourages the plant to make flowers, then form and swell the peppers. In fact, if you keep using a fertilizer that’s full of nitrogen once the plant is making fruit, it’s a really typical reason for getting lots of leaves and no peppers; the plant will grow a big, healthy green bush but won’t put its energy into making the actual fruit.

Harvest Frequently to Keep the Plant Producing

When you let peppers fully ripen on the plant, the plant thinks it’s done its job of making more peppers and will start to make fewer flowers and fruits. But if you pick peppers as soon as they’re big enough to use, most of the time when they’re green for cooking, or just as they are beginning to change color for a sweeter taste, the plant will keep on producing all season. Taking them off regularly is especially good for lots of pepper types – jalapeños, serranos, banana peppers for example – as they can have loads of peppers growing at once, and will really slow down at making more if you don’t get the ones that are there.

 

Provide Consistent Water Without Overdoing It

Peppers do best when the soil is regularly and fairly damp; aim for about one to two inches of water each week. You can get this water to them using drip irrigation or by being careful to water at the very bottom of the plant. If you let the soil get really dry and then suddenly flood it, or go back and forth between these extremes, you’ll get blossom end rot, flowers will fall off, and your peppers won’t grow to a good size. But giving them too much water will cause the roots to rot and also makes it harder for fruit to actually develop. Putting three to four inches of straw or broken-down leaves around the plants as mulch will help the soil stay at an even moisture level between waterings, and you won’t have to water quite as often on very hot days.

Key Takeaway

To get the most peppers you can, the soil needs to be nicely warm (at least 70 degrees) when you put the plants in. You should also remove the very first flowers that appear, so the plant gets stronger. Then, when it starts to flower, change your plant food to one that has more phosphorus and potassium, rather than nitrogen. Pick the peppers often to keep the plant making more, and keep the soil steadily moist with a drip irrigation system and by using mulch. Doing all of this generally means you’ll get two or three times as many peppers as you would if the soil and sunlight were the same, but you hadn’t made these changes to how you look after the plants.

Lots of people grow tomatoes at home, and most people think you need a big garden in the ground to do it. However, tomatoes in pots can be just as productive as those in a garden, if you pick the right kinds of tomatoes, use containers big enough, and are a little more careful about how much water and plant food they get. Balcony owners in apartments, people with patios, and tenants who aren’t allowed to alter the landlord’s garden…all of these people can now easily grow their own tomatoes with containers.

Choosing the Right Container Size

When you are growing tomatoes in containers, choosing the right size container is the most important thing, and is what a lot of beginners get wrong. Bush tomatoes, which are called determinate, need at least a five gallon container, which is about the size of a typical bucket for paint. Tomatoes that are vining (indeterminate) get much bigger and give you tomatoes for a longer time, so they need a ten gallon container at the very least, though they do best in pots of fifteen to twenty gallons. It’s pretty simple to understand: more soil holds onto water, and is better at keeping the temperature steady, than a little pot, and bigger roots mean bigger plants with a larger crop. Fabric grow bags, cut in half whiskey barrels, and big plastic tubs are all great for tomatoes. Whatever you use for a container absolutely has to have holes in the bottom, because tomato roots will get root rot in just a few days if they sit in water.

The Best Varieties for Container Growing

For pots, the most trustworthy choices are “bush” or compact tomato types. They grow to a set height, usually three or four feet and then stop, all their tomatoes ripen at once, and their roots do better in a restricted pot. Patio, Tiny Tim, Tumbling Tom, Bush Early Girl, and Celebrity are all varieties that have worked well for container gardeners. Cherry and grape tomatoes (Sun Gold, Supersweet 100, Sweet Million are good examples) do excellently in containers and will give you loads of tomatoes all summer long. You can successfully grow large tomatoes like Brandywine and Cherokee Purple in containers of fifteen gallons or more, but you will need strong supports for the plants and a lot more looking after.

Soil, Watering, and Feeding

When planting tomatoes in pots, use a really good potting mix. Don’t use garden soil, as it gets too solid in containers and doesn’t let water go through. For container roots to get the drainage, air, and nutrients they require, either get a mix specifically for vegetables, or a standard potting mix with added compost and perlite. The biggest problem with looking after container tomatoes is the watering. Soil in containers gets dry much more quickly than in a garden in the ground, and even more so when it’s hot or windy. Big pots during the height of summer might even need water twice a day. To avoid both not giving them enough water and giving them too much, push your finger about two inches into the soil before you water. Also, every two weeks during the growing months, give them a balanced liquid feed to replace the goodness that washes out of the soil with all the watering.

Support and Positioning

Even smaller bush-type tomatoes do well with something to lean on. A little tomato cage or three stakes forming a triangle around the plant will stop the branches, which get weighed down with tomatoes, from breaking and will also hold the developing tomatoes up and away from the surface of their container – that way they won’t get harmed by dampness or bugs. Ideally, put containers in the sunniest spot you have, giving them six to eight hours of sunshine each day. South or southwest sides of buildings are best in the north. If you put containers on plant trolleys with wheels, you can easily turn them to follow the sun as it moves across a patio during the day, or get them safely inside if the weather gets very bad.

Key Takeaway

You’ll get lots of tomatoes from plants grown in pots if the pots are big enough – at least 5 gallons for bush (determinate) types, and 10 to 15 gallons for vining (indeterminate) ones. They need to be in good quality potting mix, watered regularly, and in hot weather you may have to water them twice a day. You should feed them with liquid fertilizer every couple of weeks. Bushy, smaller determinate kinds and cherry tomatoes are the ones that do best in containers. And to finish up what your tomato plants need for a good crop of tomatoes in pots, they love being in sunshine all day, a strong support to lean on, and soil that drains well.