The most common reason for basil wilting is because of dry soil. Basil requires porous, moist soil and frequent watering in hot weather to prevent a wilting or drooping appearance. Small pots dry too quickly in the sun and cause basil to wilt. Soil that is consistently boggy can also cause wilting.
Basil is a herbaceous plant that require moist, nutrient rich soil to grow its best. Other reasons that can cause basil to wilt or droop are:
- Not watering frequently enough in hot weather
- Too much moisture caused by slow draining soils, or pots without good drainage
- Planting basil in small pots that heat up quickly in full sun and dry out
- Wilting after flowering or towards the end of the growing season (basil herbaceous is an annual)
- Fluctuations in temperature (such as a cold snap or heat wave)
- Transplant shock as there can be a contrast (in terms of temperature, light, watering etc.) between the conditions of the garden center and the conditions of your garden
- A lack of regular pruning can cause a wilting or drooping appearance
Always plant basil in full sun (6 or more hours a day) for a healthy resilient plant.
Keep reading to learn what specifically is causing your basil to wilt and how to solve the problem…
Not Watering Basil Frequently Enough
Basil is leafy herb that has adapted to grow in soil that is consistently moist yet well draining.
This balance of a moist yet well draining growing soil profile is achieved with porous, friable compost and frequent watering.
If basil dries out for any length of time it will wilt rather quickly due to those proportionally large leaves (and lack of woody stems) that transpire lots of water.
If the soil has dried out to the touch, then water the basil immediately with a generous soak. When growing potted basil, keep watering the plant until there is water trickle of water emerging form the drainage holes in the base.
If it is a hot summers day with blazing sunshine then shade the basil during the hottest part of the day to allow it to recover from its wilted state without having to contend with scorching temperatures. After the basil has perked up, place it back in full sun and ensure the soil is kept moist.
Basil should show recover from wilt due to under watering after 2 days of moist soil and appropriate growing conditions.
Adding a mulch around the base of basil plant, such as leaf mould or well rotted manure will help to conserve moisture and add nutrients to the soil which prevents the basil from wilting.
Water basil as frequently as required to that the soil is moist to a depth of one inch, so basil plants may require daily watering on hot days to prevent the plant from wilting and watering every 3 or 4 days in cooler more overcast weather.
Always water at the base of the plant rather then overhead watering as this will help to prevent fungal disease such as powdery mildew. Water in the mornings to charge the basil with water before a hot day.
As you can see from this photo, the soil has come away from the side of the pot because it is so dry. If this is the case for your basil water it immediately and try to water proactively every few days to prevent the soil drying and the basil wilting.
Watering basil can be tricky in different climates so I wrote an article with a helpful table on, how to water basil plants to help you get the balance right.
Too Much Moisture (Soil is boggy and not well draining)
Basil requires soil that is consistently moist but it is essential that the soil drain well so that the roots of the basil plant is not sat in soil that is boggy as this can also cause the basil to wilt.
Boggy soil can be caused by:
- Planting basil in soil that is slow draining (such as clay).
- Planting basil in pots or containers that do not have drainage holes in the base (or the use of a drip tray to catch water).
Sowing or planting basil in pots is always the best option as pots give you full control over the soil profile.
I use multi-purpose compost from the garden center for growing basil as it retains water and does not contain any soil pathogens (which may be present in garden soil) such as fusarium wilt that can cause your basil to wilt.
Planting basil in pots can avoid slow draining soils or boggy soils that retain too much moisture. Consistently damp soils cause root rot and your basil can wilt and turn yellow as a sign of stress.
Plant basil in large pots or containers with drainage holes in the base so that excess water can escape and the soil can maintain the balance of moisture whilst also being well draining.
When growing basil indoors I often see people plant basil with the appropriate pots (with drainage holes in the base) but they use a drip tray or a saucer underneath the pot to catch excess water so it does not spill out onto the window sill or on furniture.
Drip trays that catches the excess water keeps the soil too boggy which can cause the basil to wilt as a sign of stress.
If you are growing basil indoors I recommend taking the pot outdoors to water the basil so that water does not spoil furniture or place a paper towel under the pot for half an hour or so until water has stopped trickling from the base of the pot.
Pot size too Small (Soil dries too Quickly and Basil Wilts)
One of the most common reasons for basil wilting is because they are planted in pots that are too small. Basil that is planted in the pots from the garden center are often too small and you should re-pot basil in a larger pot in the garden.
Basil is an adaptable herb that can grow in all sorts of pots and containers (as long as it has good drainage) but pots that are too small dry out quickly in the blazing sun.
Basil requires full sun to grow its best but small pots have less capacity for soil and therefore can hold less moisture so they tend to dry out too quickly for basil to thrive.
Also be aware that metal and plastic containers conduct heat which causes more soil evaporation and the basil to wilt quickly.
Growing basil successfully in small pots is possible if you closely monitor the levels of soil moisture and water accordingly but the plant will always be more vulnerable to drought.
The best way to prevent basil from wilting in a pot is to plant it in a larger pot or container of at least 12 inches across and use terracotta, clay or ceramic pots as these materials do not heat up quickly as opposed to metal or thin plastic pots.
Basil can be transferred into a larger pot when handled carefully and water the pot as regularly as required to keep the soil moist to prevent wilting.
(Read my article, how to revive a dying basil plant).
Basil Wilting After Flowering (Requires Pruning)
If basil is not regularly pruned for its delicious leaves then it can go to flower. The flowers are attractive to bees and have a sweet aroma so this is not necessarily a bad thing but once the plant flowers it will go to seed and stop producing new leaves.
After it goes to seed the basil often wilts and at this point the leaves are not as suitable for cooking.
Most basil cultivars are tender annuals that last only one year, but you can keep the seeds for sowing next Spring and the are often very cheap at the garden center.
Regular pruning from the top of the plant allows more light to reach lower leaves and encourages a bushier more productive basil plant that last much longer so prune regularly to keep the plant healthy and prevent it from going to seed and wilting in appearance.
For more information read my article why is my basil flowering?
Fluctuations in Temperature and Transplant Shock
Basil is a tender herb that is sensitive to fluctuations and extremes of temperature which is why most cultivars are regarded as annuals.
If there has been consistent mild temperatures followed by a sudden cold snap the basil can wilt as a sign of stress even if the temperature has not gone below freezing.
If the basil has any damage due to cold such as curling leaves or brown edges to the wilting leaves then prune these leaves off which stimulates more growth of healthy leaves and speed up recovery.
Watch this video for how to prune basil so that it stays healthy, and produces lots more tasty leaves:
Wilting Basil due to Transplant shock
It is often the contrast in temperature that causes wilting, from which the plant does stand a good chance of recovering so long as you bring the plant indoors or place it in a heated green house if there is more cold weather forecast (and place the plant back out in full sun during the day or in a sunny window).
This is common after buying your basil plant from the garden center and then planting it in your garden and can be regarded as transplant shock.
When grown from seed in a garden center or plantation, basil is often grown in a temperature controlled green house and the basil plant adapts to these specific conditions, so when you plant the basil in your garden there is a contrast in temperature, humidity, watering frequency etc. which can be a shock to your basil and cause it to wilt.
The way to overcome wilting after transplanting is to ensure the basil plant has all the care it requires and it should adapt to its new environment. This means ensuring your basil:
- Planted in full sun
- The compost is well draining yet holds onto moisture
- The basil is watered enough so that the compost stays consistently moist but not boggy (adapt the frequency of your watering according to the weather)
- Protect the basil from adverse weather conditions (such as high winds, heavy rain, cold weather) by bringing the pot under shelter.
If your make some adjustments so that the basil has the right conditions to grow then basil should show signs of recovery from transplant shock within a few days and hopefully should look much better after 2 weeks.
In the same way that a sudden cold snap affects basil, high temperatures can also cause wilting.
Basil is native to tropical regions in Africa and South East Asia so it can tolerate high temperatures as long as the soil is kept moist.
If you allow the soil to dry out in hot weather the plant becomes stressed and quickly wilts but can recover with a good soak and monitoring of moisture levels.
The wilting in high temperatures may be due to variability of temperature if the weather changes quickly rather then it suffering because of the heat so ensure that it is watered so that the soil is consistently moist (but not boggy) and if the basil is planted good compost that retains moisture the plant should recover,
I would recommend the use of mulch where possible if your basil is wilting in high temperatures. A mulch on the surface of the soil surrounding the basil will help to keep the soil cool and moist in hot weather.
Materials that are great for mulching around basil plants are compost, leaf mould and well rotted manure as they all retain moisture and contribute nutrients to the soil to keep the basil plant healthy.
Prune Basil Regularly to Prevent it Wilting
Basil is a relatively fast growing leaf herb, therefore it requires a nutrient rich soil to grow its best.
Good healthy soil enriched with amendments such as alfalfa or an all purpose nitrogen fertilizer stimulates growth for more leaves so you can harvest more regularly.
However with generous amounts of nitrogen the plant can grow quickly and droop under its own weight (as the stems are herbaceous) if it is not harvested regularly.
Keep up regular pruning and harvest the top leaves to ensure the basil grows properly and with a few basil plants there may be more leaves then you can possibly cook with!
Basil can turn leggy for several reasons so I wrote another article about leggy basil to help you to solve the problem and revive leggy basil.
- The reason basil plants wilt is because of dry soil. Basil requires moist soil and frequent watering in hot weather to stay healthy. However basil can also wilt due to soil that is boggy rather then moist and well draining. Boggy soil causes basil to wilt and turn yellow as a sign of stress.
- If basil is planted in small pots the soil dries out quickly in the sun causing the basil to wilt. Larger pots have more capacity for soil and moisture to prevent the basil from wilting.
- Basil is sensitive to fluctuations in temperature. Extremes of hot and cold can cause wilting. Snip away any leaves that have been damaged by the cold and bring the basil indoors to protect it until the temperature increases. Basil that that has wilted in high temperatures will recover with frequent watering. Snip away leggy growth before it flowers to prevent the basil from wilting in appearance.
- Transplant shock can also cause a basil to wilt due to a contrast in conditions from a garden center to your garden. Give basil some time to adjust and ensure it is planted in full sun with compost that retains water, yet is well draining and the plant should recover from a wilting appearance.
- Basil that is planted in rich soil and has had many applications of fertilizer can grow leggy and droop in appearance, particularly if it is not regularly pruned. Harvest the top leaves of the basil planted regularly to ensure a good shape and to prevent the plant from drooping. Harvesting the leaves keeps the plant from drooping under its own weight and stimulates growth from lower leaves.