Basil plants are a fairly common staple in the garden of most warm climate gardeners. While many people think of basil as an Italian plant, the truth is that there are varieties of basil all over the world.
The plant has different flavors depending on where each type of basil originates, but nearly all versions of the plant have similar growth patterns. That means that no matter what type of basil you’ve planted in your garden, odds are good that if you’re having problems another gardener has experienced the same thing.
If your basil is wilting, there is likely a good explanation, and fortunately, other gardeners who have had this problem know how to fix it. If your basil is wilting, check to see if the cause might be one of these common culprits.
Related To: How to Bring a Dead Basil Plant
1. Temperature Drop
Basil is a plant that is native to warmer climates around the world (think Italy, Greece, or Thailand) and it can be particularly sensitive to freezing temperatures. If your basil was planted outside and it has experienced a sudden temperature drop, especially a sudden freeze, it likely started dropping leaves the next day.
After the leaf drop, the remaining stems will eventually start to grow leaves again. Be aware that if the temperature gets too warm the plant will bolt.
To mitigate the damage, after the temperature warms up, trim off everything on the plant that is showing signs of frostbite. This includes all leaves and stems. Don’t worry about overpruning at this point, the important thing is to remove the damaged part of the plant.
2. Lack of Sunlight
Because the plant is native to areas of the world with higher temperatures, basil is best suited to getting at least six hours of full sun every day. If your plant isn’t getting enough sunlight, it’s very likely that it is looking sickly and droopy. This is a common occurrence in basil plants that are grown indoors and those that are growing under the shadow of tall trees and shrubs.
Plants that are not receiving enough sunlight can appear to be sickly, but it is actually growing towards whatever light it can find. This often results in a plant that appears to be leaning. Leaves will only tend to grow on the side that gets enough sunlight.
The best way to solve this issue is to transplant the basil into a sunnier area. To transplant, start by digging a circle around the base of the plant that has the same radius as the height of the basil plant.
This should provide enough space to get the entirety of the root structure under the plant. Dig a hole of the same radius in the area that you want to move the plant to, and move the plant to its new location as soon as it comes out of the ground. The less time the plant root spends exposed to the air the better.
If you cannot transplant the basil, look for ways to reduce the amount of shade the plant is in. For example, start by trimming back the surrounding branches and bushes from neighboring trees and bushes that are providing shade. If a plant is indoors, turn it periodically so that all sides of the plant receive sunlight.
Once you’ve established the plant in good sunlight, snip off any leaves and stems that are yellow or brown. You may also want to cut back any stems on the plant that have grown too tall.
This will encourage the plant to grow out and produce more harvestable leaves. During the period of recovery from low sunlight, try not to take more than one or two leaves a day. Allow the leaves to absorb enough sunlight to assist the growth of the plant.
3. Over-watering
As soon as you transplant basil into a new location, make sure it is watered very well. Unfortunately, this direction can lead to over-watering the plant, which can also cause problems with wilting.
When you’re over-watering or the soil has poor drainage, basil will be affected by being in too much water with root rot. Since no one can see the actual condition of the roots, the first sign that there is a problem will be when the plant’s leaves and stems start to turn brown.
Eventually, these leaves will fall off the plant and in extreme cases the plant’s stems will die. This can occur because the plant’s roots cannot get enough nutrition to the upper parts of the plant.
Unfortunately, there isn’t a lot that can be done about overwatering or root rot. If the plant is just slightly overwatered, the odds are good that it will recover on its own once the soil around it starts to dry. If root rot has completely set in, however, there isn’t much that can be done.
Sometimes aggressively pruning back the plant will help, as healthier parts of the roots are able to support a smaller plant, but be prepared to lose the plant.
In particular, snip off any leaves and stems that are already starting to die; these parts of the plants are already unable to receive nutrition, and it will help the plant to remove the diseased parts and focus on building the health of the main plant.
4. Underwatering
If your basil plant hasn’t received enough water, it will likely have issues with leaves turning yellow, then shriveling and turning brown before eventually falling off. Fortunately, basil is a plant that tends to recover quickly after short periods of drought.
If you haven’t received enough rain in your outdoor garden, or if you just forgot to water your plants, odds are good that your basil will recover. A few words about watering though. To start, basil tends to do best when the soil around it is watered.
Try to avoid pouring water directly on top of the plant, and especially try to avoid drowning the leaves. Like many other plants with broad leaves, it is easy for moisture to get trapped inside the curls of leaves and start rotting the leaves. This is especially the case with basil that is grown in partial shade.
Keep the soil around your basil plant moist; in fact, it’s a good idea to water the plant as soon as the soil starts to appear dry. Again, remember to pour the water directly onto the ground, and stop once the soil appears wet.
5. Lack of Pruning
It can seem to go against logic to remove the leaves of a plant in order to get it to grow more, but it really is the best way to get basil to produce more harvestable leaves. In the early growth stage of the plant, the common advice is to pick leaves as needed; even on a new plant this should be enough to stimulate growth.
Don’t make the mistake of assuming that basil does not need to be pruned because it is occasionally harvested. Avid gardeners will inspect their plants at least twice a week or more to look for signs that it may be time to prune. If you are not ready to use the basil right away, learn how to dry the leaves and preserve them for later use.
Cut off or remove any leaf or stem that is showing signs of rot, disease, or sun spots. While these leaves can recover, it rarely makes sense to let a basil put the energy into repairing a leaf. Removing the leaf will encourage the plant to make more leaves, giving you more basil available for harvesting.
By the way, yellow or brown leaves that are removed from the plant are rarely good for anything. Try not to use them in recipes or cleaning products, as they might have disease or parasites that can transfer to humans. You can remove bad spots from leaves, however, and use the healthy parts. If the leaf is very badly damaged, however, add it to the compost pile rather than try to use it.
If you find it hard to determine how much to harvest from a plant like basil, follow the 10% rule. No matter how often you harvest an herb, never take more than 10% of the plant in a single day. Following this rule usually ensures that you’ll have enough leaves per day to cook with for your family, but it also allows the plant enough left over leaves to keep the plant healthy.
When following this rule, you don’t have to worry about which leaves to pull. If you clip a single large leaf or several smaller ones, the plant will stay just as healthy as it was before. In all the years I’ve grown basil, I’ve been able to maintain healthy plants for years by never taking more than 10% of the leaves in a single day.
Of course, this can be a very time-consuming rule if you need to harvest your plants for a large meal or dry out the leaves for use later. This rule comes from a time when it was normal for women and children to use a kitchen garden on a daily basis, so daily harvesting of basil wasn’t considered to be particularly unusual or a burden.
While there are still plenty of home gardeners who take the time to harvest a few leaves from their plants everyday, then take the time to individually dry everything, it is important to know how to harvest a lot of basil at one time and maintain the health of your plant.
To harvest a large amount of basil, use pruning shears to cut the top stems and leaves off of the plant. The top tends to be the most recent growth, and the plant will be able to grow out from the leaves and stems that are remaining. Pull individual leaves off of what you cut off to use in recipes or dry; compost the stems.
Next, remove all of the large leaves from the remaining plant. Large leaves tend to block sunlight from reaching the smaller leaves, making it difficult for them to be healthy and grow. The remaining plant will have small leaves, but it will grow quickly (if the plant is healthy) and it should be ready to harvest again within a month.
6. Over-pruning
If you have never pruned your basil plant before, it’s entirely possible that you trimmed it too far back when you decided to harvest. Without any leaves, it will take basil a long time to process the sunlight it needs to keep a complex root system going through the stem alone. While this will not typically kill the plant, it may take several months for the plant to recover to the point that it can be harvested again.
In general, I recommend the 10% method to new gardeners in order to avoid this problem. By taking no more than 10% of the leaves on a plant per day, it’s almost guaranteed that you will not have issues with over pruning. Even if you have already trimmed the plant back too far, this method will ensure that you do not repeat the mistake.
7. End of Life
Like all living things, basil plants have a natural life cycle. If you have checked all of the other things on this list, it might be time to accept that your basil plant has reached the end of its natural life.
Typically, basil will bolt, or form flowers, as it nears the end of the time it can be productive for. As it forms flowers, the leaves will become very bitter, making them unsuitable for use in most cooking. Be aware, however, that the oil can still be harvested from the leaves, and the leaves can still be used for most medicinal, cleaning, and scent purposes.
As the flowers mature and start to produce seeds the leaves of the plant will wilt and start to fall off. If the plant is pollinated correctly, it is possible to harvest the seeds and use them to start a new plant.
