Categories
BLOG

my weed plant is wilting

Watering Your Cannabis: How To Fix Over And Underwatering

Overwatering and under watering your cannabis plants can cause multiple symptoms and may even slow down growth. It’s all about understanding your plants and finding a sweet spot. We explore how to recognize and fix these issues, as well as take a look at the importance of water quality in general.

Contents:

There are many contributing factors involved when it comes to a successful and bountiful cannabis grow. Lighting, nutrients, airflow, and humidity all play important roles in optimal growth and vibrancy of a crop. Water, however, is one of the most important aspects of keeping cannabis plants healthy and strong.

Watering isn’t always as simple as it may seem. Many growers are under the impression that completely saturating their crop with water each day is all it takes to help plants obtain their aquatic requirements.

The truth is, there is much more to the watering process. Watering cannabis plants is a balancing act that takes some time and experimentation to perfect. Too much water can lead to some serious problems for plants and may obstruct oxygen intake. On the other end of the spectrum, too little water can lead to extremely dry conditions that will leave cannabis plants thirsty, eventually causing them to wilt.

We take a look how to recognise if you are over or under watering, and how to fix it.

OVERWATERING YOUR PLANTS

Overwatering is an easy mistake to make when growing cannabis, and is most likely caused by worrying that plants need constant doses of water. It is a pitfall novice often fall into.

Cannabis plants actually use their root systems to breath air, in addition to uptaking water, and if their roots are constantly swamped in water, they will begin to drown.

1. One primary symptom of overwatering is drooping leaves. However, it is not the same kind of droop you see when underwatered – where leaves look wilted. It is the opposite in fact. Leaves are so full of water, that they are being forced to curl in on themselves. It results in them becoming very firm.

2. Additionally, the rate of growth of overwatered plants will slow down dramatically or may even come to almost a complete halt. This is due to the anaerobic conditions that arise due to the lack of oxygen accessible to the root system.

3. Another symptom of overwatering a cannabis plant is yellowing of the leaves. This is a sign of a nutrient problem, that is a side-effect of overwatering.

If you are experiencing any of these symptoms within your plants and believe the root cause is overwatering, the best thing to do is water less often. Wait for the top layer of soil to look and feel dry before watering again. A good test is to put your index finger in the soil up to the knuckle. if it is dry, consider watering.

Also, make sure each plant has adequate drainage and that water isn’t building up too much in the bottom of the pots or containers that they are housed within. You want excess water to drain out of the containers, leaving soil moist but not waterlogged.

UNDERWATERING YOUR PLANTS

1. Underwatered cannabis plants will look very weak, lifeless, and will show signs of wilting. Its no wonder they begin to look this way considering the vital role of water in plant physiology. The wilting of underwatered cannabis is different from the plump curling of overwatering – even if only subtly. Leaves will be fragile, brittle and even papery. They will look lifeless and drab. Another sign of an under watered cannabis plant an extremely dry growing medium, such as crispy soil.

2. Underwatering occurs when growers simply aren’t meeting their plant’s demands. Without adequate water, the root system will dry up and growth and yield may be reduced. Be sure to water your plant when the top inch of soil has dried out. Leaving it any longer than this may start to have detrimental effects.

3. One aspect that may cause underwatering is not using the correct pot size at certain stages of growth. For example, growing a small seedling in a large pot may reduce the plant’s chances of uptaking enough water, as the small root system doesn’t have a chance to uptake water before it drains away.

WATER QUALITY IS PARAMOUNT

As well as watering frequency, the quality of the water used to supply a cannabis crop is also a highly important consideration.

Cannabis plants consist of approximately 90% water, and the substance is required during various vital physiological process such as photosynthesis and transpiration. When using a poor quality water source to supply cannabis plants, these processes may be less efficient than they can be, or in worst case scenarios, disruptive.

When these disruptions occur, symptoms may manifest that appear almost identical to an array of other conditions such as over or under fertilisation, under-watering, and possibly even heat stress. This is a perfect example of why to always double and triple check the root cause of the problem when troubleshooting health issue of cannabis plants.

HOW OFTEN DO YOU NEED TO WATER YOUR PLANTS?

This question actually has many different answers, as many different variables are at play. For this reason, there is no exact answer. For example, temperature, humidity, and other environmental factors can all change how often water will be required.

However, there are telltale signs that will display it’s time to once again water your plants. Checking the top inch of soil is a promising way to identify this. Wait for this section of the soil to be dry before watering again in order to avoid overwatering. Once you have done so multiple times, you should start to figure out how long it takes in between each watering, and then you can go by that length of time instead.

Paying close attention to your plants leaves is another way to tell if its time to water. Of course, waiting long enough to symptoms to arrive is not optimal, but any signs of wilting should immediately be followed by a dose of water.

MONITOR PH

Before the growing process, check the quality of your water source. One important factor when it comes to water quality is pH. pH is a numeric scale used to measure the acidity or alkalinity of a solution, with the middle value of 7 representing neutral. Numbers less than 7 represent acidity and numbers above 7 display alkalinity.

PH that is either too high or too low can cause problems in cannabis plants, as the pH of the water source can dictate a plant’s ability to absorb nutrients. Too low or too high pH water can affect the pH of your grow medium over time, which results in symptoms that look identical to those caused by certain nutritional problems.

Cannabis plants tend to thrive at a pH of around 6.5. pH can be measured extremely easily by simply applying a pH metre around a water runoff sample. Runoff is water that drains from your grow container, having passed through your grow medium. If the pH is either too high or too low, pH up and down products can be used to return it to normal levels.

PPM is another important factor when it comes to water quality. Ppm, or parts per million, is a method of measuring the amount of minerals that have dissolved into the water source being used. So, a reading of 90ppm will indicate that there are 90 milligrams per litre of minerals present within the water source.

Being aware of the PPM within water allows growers to avoid giving their plants too many or too little minerals. A lack of minerals may lead to deficiencies, whereas too many may cause burning to occur. Cannabis plants prefer a ppm of around 500 when in the vegetative phase, and favour a ppm of around 1000 during the flowering stage of the grow cycle.

TDS meters, devices that measure total dissolved solids, can be used to measure the ppm of a water source.

Monitoring ppm is quite advanced, and while useful, is not essential for novices finding their feet. Just bear it in mind as you look to expand your knowledge and skill.

REVERSE OSMOSIS WATER

Although the total dissolved solids within your water profile might be adequate, not all substances within a water source are beneficial for your cannabis crop. Water might be contaminated with other factors such as pollutants and bacteria. Reverse osmosis filters are a great option to almost completely remove everything within a water source, allowing growers to add back only what they want their plants to come into contact with.

Reverse osmosis filters are capable of removing between 95-99% of dissolved salts within a water sample and is therefore a standard method of cleaning water on an industrial scale.

Once again, using reverse osmosis water is an advanced growing technique.

With the above in mind, you should be well on your way to understanding how over and underwatering affects your plants – as well as overall water quality in general.

TESTING YOUR WATER RUNOFF

To produce healthy plants, you need to keep a close eye on the amount of nutrients your plants are receiving. To do this, use trays to catch the runoff when you water your plants, and analyse both its pH and PPM (parts per million).

WHAT PH SHOULD YOUR RUNOFF BE?

Cannabis plants tend to thrive at a pH of around 6.5. To check your pH, simply test the runoff using a pH meter. Our pH tester by Hanna Instruments is super simple to use and offers fast and accurate readings. If your pH is either too high or too low, you can use pH regulators to bring it up or down.

Too many fertiliser salts can obstruct nutrient uptake and cause wilting. Use the DiST 4 Pocket Conductivity Tester for accurate readings.

Too many fertiliser salts can obstruct nutrient uptake and cause wilting. Use the DiST 4 Pocket Conductivity Tester for accurate readings.

We explore how to recognise and fix cannabis over and underwatering, as well as the importance of good quality water.

How To Revive Sick Cannabis Plants

When your cannabis plants are sick and stressed, it’s important to immediately identify the problem. That’s when the real process of reviving your cannabis begins. Here’s what to do to help your plants recover and thrive after a major setback.

Contents:

Your plant is wilting, you notice the leaves turning yellow or forming unsightly spots, or maybe it’s refusing to grow altogether. There are many reasons why cannabis plants can become sick, from issues with watering to pest infestations, inadequate lighting, heat stress, and more.

No matter the reason for your plant’s sickness, the first thing you’ll want to do is diagnose the problem. When you have addressed the cause(s) of your plant’s condition, you obviously want to revive it as fast as possible. Here are some things you can do to help plants recover from infestations, illness, and more.

PROBLEMS IN YOUR GROWING ENVIRONMENT

If your plant appears to be dying or suffering hard, it is unlikely that a minor issue is occurring. Most of the time, a rapid descent in the health of your plant signals a fundamental issue or invasion. This can involve problems with environmental conditions, microscopic infestations, and other culprits.

CHECK TEMPERATURES AND HUMIDITY IN YOUR GROW ROOM

If you’re growing indoors, the first step to reviving your plants is to check the temperature and relative humidity of your tent or grow room. The ideal temperature for cuttings and seedlings is between 20–25ºC. As the plants get older, they can tolerate a bit more, up to 28ºC. Everything above this is excessive and causes stress, which will make it much more difficult for your plants to recover.

Likewise, the humidity levels of your room must be kept within a certain range depending on the phase of growth. An optimal humidity level for flowering plants is 40–50%. Plants in the vegetative growth phase can tolerate a more humid environment, from 40–70%. If the humidity is too high, you need to look into better ventilation for your grow space. A dehumidifier is the best, albeit expensive option here. Your sick plants will have a hard time recovering if their environment is not stable and optimal.

AVOID HEAT STRESS OUTDOORS

Despite cannabis loves plenty of light and warm temperatures, if you grow outdoors in the summer, heat stress and excessive sun can be a problem, especially for plants recovering from illness. If you have your plants in pots and they look stressed from too much heat, move them to a shadier location. Less heat and direct sun will make it easier for sick plants to get back up to strength.

LOWER YOUR LIGHT LEVELS

Cultivators normally keep their wattage levels as high as possible to encourage plants to grow faster. More light means the plant is working harder and will likely produce a greater yield. On the other hand, a plant that is working extra hard is more susceptible to deficiencies and other problems. One way to give your sick plant a break is to decrease the light intensity. Move your lights higher up and further away from your plants, or decrease the wattage.

When you grow indoors with your lights on a timer, you can also cut down on the daily light hours your plants receive. When you reduce the light hours for the vegetative phase to only 17 or 16 a day, this will give your plants more time to “rest” and recover.

FLUSH YOUR PLANTS

Many problems with sick cannabis plants can be due to overfeeding. When your plant can’t take up the nutrients that you provide, salts and minerals will accumulate in the soil over time. This will change the pH level at your plant’s root zone, making it more acidic—beyond the small pH window that cannabis has for healthy growth. As a result, your plant is not able to take in nutrients, even if they are present in abundance. When this happens, further feeding only makes it worse.

In almost all cases where your plants show signs of nutrient deficiencies or nutrient burn, you should give your plants a solid flush. Flushing means that you rinse out the excessive salts with pure, pH-balanced water to restore the optimal pH of the growing medium.

To flush your plants, drench the growing medium with water numerous times. It should be ample enough that liquid comes out from the bottom of the container each time. For example, if you grow in 7l pots, flush your plants with 14l of water. When you grow in soil, your water should have a pH of about 6.5pH. After the flush, you can begin giving nutrients again, starting with ½ or ¾-strength doses. You can slowly work your way up from here to avoid putting plants under any additional stress.

REPOT YOUR PLANTS

Repotting your cannabis plants into new, larger containers with fresh soil can also help bring them back to life. Choose a container that has plenty of room for the roots to grow. If your plant is severely damaged due to overwatering (root rot) or various fungi, consider trimming its foliage. When the roots have fewer leaves to support, they can recover faster.

KEEP PESTS AWAY

Plant infestations from spider mites, fungus gnats, fruit flies, and other insects are all too common when you grow cannabis. When you have finally gotten rid of the pests, you want to make absolutely sure that they don’t return. Pest infestations can really ravage a plant, so it certainly needs optimal care and time to be revived.

In terms of keeping the pests away, there are natural insecticides like neem oil that can be highly effective. You can even use it as a foliar spray, applying it to your leaves every 2 or 3 weeks. However, be careful during the flowering phase as you do not want the overbearing taste of neem oil on your buds! For fungus gnats, you can also set up yellow sticky traps, which will catch most of them.

Neem oil serves as a completely natural way to protect your cannabis plants against pests.

Neem oil serves as a completely natural way to protect your cannabis plants against pests.

SUPPLEMENTS TO HELP YOUR SICK PLANTS RECOVER

There are certain supplements you can give to your sick plants to reduce stress, support their development, and increase their resistance.

Compost Teas

For those growing in soil, compost teas are an excellent supplement to support the recovery of sick and stressed plants. Compost teas can make your plants grow faster and more robust, making them less susceptible to diseases and deficiencies. Some cultivators make their own compost teas at home, although they can also be purchased at most well-sorted grow stores.

Silica

Silica has properties that strengthen the cell walls of your plants, which makes it helpful for increasing their resilience. Furthermore, it makes certain minerals and nutrients more available while protecting the roots as well.

Seaweed

Seaweed contains minerals and other micronutrients, and has been shown to help reduce plant stress. While its mechanism is somewhat unknown, seaweed has long been part of the weed grower’s arsenal.

With the above tips, we hope you are able to revive your precious cannabis plants and make it to a hefty and healthy harvest.

In this guide, you'll learn how to help revive your sick and stressed cannabis plants after infestations, nutrient deficiencies, and much more!