Overwatered Basil: Signs of Trouble & 7 Easy Rescue Tips
(This post may include affiliate links. While buying items through these links won’t increase your cost at all, we may receive a small commission that helps keep this site up and running. See our Terms and Conditions page for more details)
Some of the most common plants in a home garden are herbs, and basil is often one that tops the must-grow list. It definitely does for me! Even though it’s usually a low-maintenance plant, it can be easy to give your basil too much water without even realizing it until there’s a problem.
Signs of overwatered basil include yellowing lower leaves, stems drooping, stunted growth, outer leaves turning brown or black, and the soil feeling wet hours after watering. If the overwatering is mild, your plant should recover, but if the problem is severe and the roots are damaged, it will likely not survive.
Overwatering is a serious problem for plants- in my opinion, it’s probably the #1 cause of death. So in this post, I’m talking about how to recognize the signs that your basil has too much moisture and what you can do about it. You’ll also learn how to avoid the opposite issue- under-watering- and how to plan a good watering routine for your basil garden.
Let’s get started!
- Signs of an overwatered basil plant include yellow base leaves, drooping stems, stunted plant growth, leaves turning brown, and soil that consistently feels wet.
- Stop watering until the soil feels dry 2 inches deep. Move potted basil plants to a sheltered location if more rain is forecast.
- Increase the sun exposure and airflow to your basil plant to help the excess moisture dissipate.
- If potted basil lacks drainage or has dense soil, repot in a new planter with fresh soil. For basil in the garden, work organic matter into the top couple of inches of soil to improve texture and drainage.
- Resist the urge to prune away damaged sections until the plant shows signs of recovery.
- If the basil does not improve, pull it and dispose of it in the trash.
- Basil likes to get about 1.5 inches of water weekly. Water the soil, not the leaves.
- Growing basil hydroponically is a great way to eliminate overwatering.
What Does Overwatered Basil Look Like? 5 Signs to Look For
The first step in treating an overwatered basil plant is recognizing the problem. Here are the signs I’ve observed in overwatered plants.
1. Leaves At the Base of the Plant Are Turning Yellow
Often times, basil leaves turning yellow is the first indication of overwatering. What’s happening is your basil plant is experiencing stress from the roots being surrounded by too much water. So the plant cuts off resources to the older leaves, which are the ones near the base, to conserve resources for new growth.
2. Stems Drooping or Wilting
Basil is an herbaceous plant, meaning that its stems are soft, water-filled tissue rather than tough woody fibers. When those stems get overloaded with moisture, they can’t hold themselves up properly, so they droop over.
3. Slow or Non-Existent Growth
I’ve always found basil to be a pretty fast grower, so if it’s not putting out noticeable new growth every few days, there’s likely a problem.
Plant roots absorb nutrients, water, and air from the soil. But when the soil is saturated with water, the roots can’t do their job properly, and the plant can’t produce new leaves.
4. Outer Leaves Turning Brown or Black
Black spots on basil is a later sign of trouble, and it happens because the roots are not just struggling to keep up, they’re actively dying off from a condition called root rot. Root rot happens when harmful microbes multiply in wet soil, attacking the roots and causing death.
Once the roots can’t support the plant anymore, the leaves will start dying- hence, the brown and black discoloration.
5. The Soil Feels Wet Even If It’s Been Hours After Watering
There are a few things that could be going on here:
- You may have watered too aggressively for several days in a row.
- A cloudy, rainy weather pattern has settled over your region for several days.
- Your garden soil could be compacted or have a heavy clay component that prevents water from draining properly.
- Potted basil plants could have an obstruction that isn’t allowing for drainage.
- There may be leftover water sitting in the dish below potted basil.
7 Ways Help an Overwatered Basil Plant
I’ve always found basil to be a resilient plant. As long as the damage isn’t too far progressed, it stands a good chance of recovery. Here’s what I recommend to help:
1. Stop All Watering Immediately
This one is simple but critical. Do not give any more water until the soil feels dry 2 inches deep. If you have a potted basil plant and more rain is in the forecast, move it where it won’t get more rainfall.
2. Increase Sun Exposure
More sunlight can help your plant process the excess moisture a bit faster, and it can also help speed up evaporation.
If you’ve got your basil in a pot, this is pretty easy- move it to a brighter location. But if your basil is in the ground or a raised bed, you’re more limited. You can always try transplanting into a sunnier location, or look for any tall neighboring plants you might be willing to cut back.
3. Promote Airflow
In my experience, a lack of airflow often goes hand-in-hand with a lack of sunlight. When I’ve tried to grow plants in odd, sheltered corners, I’ve run into trouble with soil staying damp and plants not doing well. If you’ve got your basil in a spot like this, transplanting could be a good option.
Also, make sure there aren’t weeds crowding the basil and keeping the airflow stifled.
4. Repot Potted Basil
Look at the soil and the drainage in your current pot. The soil should be loose, and there should be at least one large, unobstructed drainage hole. If these things aren’t the case, repot your basil into a new pot with good drainage and fresh potting soil.
5. Loosen Garden Soil and Add Organic Matter
For basil in the garden, use a trowel or hand rake to gently break up compacted soil around your basil plant. You’ll only be able to go a couple of inches deep at most- be careful not to disturb the roots.
Next, add some organic matter to the soil to help improve the texture. These are some good ones:
- Well-aged manure
- Shredded leaves (ideally aged from the previous fall)
- Grass clippings from untreated lawns
6. Don’t Prune Damaged Sections Right Away
I always give a stressed plant a couple of days to recover before I cut off damaged sections. Pruning itself can cause more stress, and even damaged leaves can still contribute to photosynthesis.
You can prune the plant when it started to show signs of recovery, or the plant will naturally shed the affected parts on its own.
7. If Needed, Pull the Plant and Dispose of It
In cases where root rot has taken hold, you may not be able to save your basil plant.
If you don’t see any improvement in a few days or the problem just gets worse, pull the plant and dispose of it in the trash. While root rot probably won’t spread if you put the plant in the compost, I don’t see a reason to take a chance.
How to Water Basil the Right Way
I’ve covered this topic in much greater detail in my post on basil water requirements, but here are a few quick tips.
Basil thrives in well-draining soil that stays evenly moist. Here’s what that means:
- The water runs down through the soil without backing up anywhere.
- The soil stays consistently damp in the root zone- about 1-2 inches down.
According to the Utah State University Extension, basil likes to get about 1.5 inches of water weekly, including rainfall.
A drip irrigation system automates the watering routine, so it’s convenient and consistent. If you want to water manually, check the soil every couple of days and water once it feels dry 1-2 inches deep. In extreme heat spells, you may need to water daily.
Either way, aim the water directly at the soil- don’t splash the leaves if you can help it. Ideally, your basil plant’s soil should be dark and damp but with no pooling water.
Watering in the early morning hours is best since it gives the plant time to absorb water before the heat of the day evaporates it all away. But if you can’t make it out then, make it a point to avoid watering during peak sun hours (usually 10 AM to 2 PM) if at all possible.
Growing Basil Hydroponically
If you want to eliminate the possibility to over water basil plants, consider using a hydroponic system. Since most herbs, including basil, stay relatively compact, they’re ideal for growing hydroponically.
In case you’re unfamiliar with hydroponics, it’s the concept of growing plants in a water-based system rather than a soil-based one. And while that sounds like a recipe for overwatering, it’s actually the opposite. Plants grown in hydroponic systems only take up the amount of the nutrient-rich water they need, and it’s always available.
Also, a hydroponic system allows you to control light exposure, temperature, humidity, and air circulation. And you can also run a hydroponic system indoors all year round, so it’s perfect if you want to enjoy some fresh basil in the dead of winter.
There are lots of options for hydroponics on a small scale that are ideal for home growers. I compiled a list of several hydroponic builds for home gardeners to give you some inspiration.
What Does Under-Watered Basil Look Like?
I feel like I can’t address overwatering without also mentioning the opposite problem: under-watering.
Can you under-water basil? Yes, it’s happened to me- in fact, it’s the problem I’m actually more likely to run into. Under-watering could also easily happen if you’re feeling a little timid after giving your plant too much water before.
Both under-watered and overwatered basil will droop and have discolored leaves, so that can be a bit confusing at first. But in my experience, overwatered plants have a squishy, saturated feel while those suffering from under-watering feel shriveled and thin.
While the leaf/stem can help you out a little, the soil is your biggest indicator of which problem is going on. Feel the soil- if it’s dry several inches deep, you have an under-watering problem.
Give your plant a good soaking right away, but do it in a few smaller doses over the span of 10-15 minutes. This gives the water a chance to slowly soak down into the soil instead of forming a big puddle that just runs off.
Frequently Asked Questions about Overwatered Basil
I hope this guide to dealing with overwatered basil has been helpful to you. It’s always disappointing to see a plant suffering. But in my own garden, I’ve had some pretty scraggly-looking basil plants rebound surprisingly well. With the proper treatment, your basil should bounce back and start producing more delicious leaves within a week or two.
I’d love to hear from you! Do you have any other questions about basil overwatering? Have you seen some basil come back from seemingly the dead- if so, what did you do to help your plant? There’s no comparison to learning from one another’s experiences and questions, so please share your thoughts in the comments!