Water annual herbs as often as required to keep the soil moist but not saturated which is usually once every 3-7 days. Mediterranean herbs should be watered less often, allowing the soil to dry out between bouts of watering. Water Mediterranean herbs once every 2 weeks in pots and containers.
The biggest and most important distinction when it comes to how often to water different types of herbs is whether they are perennial herbs originate from the Mediterranean region of Europe (lavender, rosemary, thyme, sage, oregano) or whether they are leafy annual herbs (basil, cilantro,mint, dill, chives, parsley).
Mediterranean herbs are woody and adapted to tolerate drought conditions, therefore they should only be watered once every 2 weeks at the most (once they have established).
Leafy annual herbs require the soil to be consistently moist (but not saturated) so they show be water much more often (once every 5 days or so depending on conditions).
Here is a table to use as a quick reference guide for how often to water herbs at different times and conditions…
|Conditions||How Often to Water Herbs|
|How often to water Mediterranean herbs:||Water every 2 weeks in if pots. Do not need watering once established (after 1 year) unless exceptional drought.|
|How often to water annual herbs:||Water as frequently as required to keep the soil moist at 1 inch depth (typically every 3-7 days depending on sun and temperature).|
|How often to water herbs after planting:||Water leafy herbs every 2-5 days to keep the soil moist but not saturated. Water Mediterranean herbs once every week for the first 4 weeks after planting.|
|How often to water herbs indoors:||Water herbs such as basil and cilantro every 5-7 days indoors.|
|How often to water herbs outdoors:||Water outdoor annual herbs once every 5-7 days or so if there has been no significant rainfall. Water Mediterranean herbs once every 2 weeks in pot and do not water once established unless exceptional drought.|
|How often to water in pots:||Pots outdoors dry out quicker then pots indoors. Water outdoor pots once every 2 weeks for Mediterranean herbs and once every 3-7 days for leafy annual herbs.|
|How often to water herb seeds:||Water as often as required to keep the soil moist, ensuring the soil does not dry out (typically once every 3 days).|
|How often to water herbs in Summer:||At the hottest times of year water annual herbs (such as basil and cilantro) as often as required to keep the soil moist which could be once every 2 days. Mediterranean herbs thrive in Summer so water once every 2 weeks as normal.|
|How often to water herbs in Winter:||Perennial herbs outdoors do not need any additional water in Winter as this increases the risk of root rot.|
It is important to note this table is a guide and there are several variables that can affect how often to water herbs such as the size of the pot, temperature and the hours and intensity of sun.
Keep reading to ensure you are watering your herbs with the right frequency in different conditions to keep the plant healthy…
How Often to Water Mediterranean Herbs
Water potted Mediterranean herbs such as lavender and rosemary once every two weeks during Summer. Established Mediterranean herbs in vegetable gardens should only be watered in extreme drought as they are drought resistant and can attain all the moisture they need from rainfall.
Mediterranean herbs refers to any herb that is native to the Mediterranean region of Southern Europe and has adapted to the hot and dry climate during the Spring and Summer and mild Winter with infrequent rainfall.
Popular Mediterranean herbs include:
All these herbs thrive in dryer conditions and therefore should be watered significantly less often then leafy annual herbs.
Watering Mediterranean herbs too often promotes the conditions for the fungal disease Phytophthora root rot to thrive.
As Mediterranean herbs are adapted to dryer soil conditions, there are particularly susceptible to root rot therefore it is very important that you try replicate their natural conditions by watering them less often then other plants.
Water once every two weeks when they are in pots (with a generous soak to promote root development) as pots tend to dry out quickly in the summer particularly if they are smaller then 12 inches across.
Mediterranean herbs (such as lavender) tend to be perennials which means they come back every year as long as they are cared for in Winter by protecting them against cold temperatures and not watering them at all.
Mediterranean herbs attain all the water the need in Winter from the environment and are at greater risk of root rot so you can stop watering herbs such as rosemary and sage in the Fall, until the following spring.
Mediterranean herbs that are planted in raised beds or as hedges in garden boarders do not require any watering at all once they have established after the first year as they are capable of thriving in hot and dry Summers of Southern Europe without any need for watering.
How Often to Water Leafy Annual Herbs
Water herbs such as basil and cilantro every 3-5 days to ensure that the soil is consistently moist to prevent them from wilting. During the hottest times of the year water your annual herbs as often as every other day, particularly if they are in small pots outdoors.
Types of popular annual herbs inculde:
Annual herbs such as these may be used in Mediterranean cooking but actually originate in other parts of the world where they thrive in moist soils with higher levels of rainfall, in partial shade.
Therefore the annual herbs require consistently moist soil and so should be watered more often then Mediterranean herbs.
With Mediterrenaean herbs the greatest risk to the plants health is watering too often whereas annual herbs are at significant risk from underwatering which results in the leaves and stems wilting.
The risk of root rot from watering too often is much less pronounced with annual herbs (compared to Mediterranean herbs) and is usually only an issue if the soil is saturated because of slow draing soils or pots without drainage.
There are several factors such as they right potting soil for annual herbs and the size of the pot that affect how often to water your annual herbs so read my articles choosing the best pots for herbs and best potting soil for herbs.
As long as these herbs are planted in organic rich compost or potting soils which drain well and planted in a large enough pot and placed in partial shade then watering once every 4-7 days is usually sufficient.
Adjust the how often you water these herbs if they start to show signs of drought stress such as leaves curling or wilting.
It should be noted that annual herbs such as basil prefer morning sun followed by afternoon shade. If they are in full sun in the afternoon then the herb may wilt temporarily (as a reaction to the heat, rather then a lack of moisture) and return to normal once temperatures have cooled in the evening.
Test the soils moisture to a fingers depth to check whether your herbs have enough moisture. If the top inch of the soil feels somewhat dry then give your herbs a good soak. This is a good way to establish the optimal watering frequency for your herbs in your garden according to the conditions rather then a generic schedule.
How Often to Water Herbs After Planting
Water annual herbs such as basil frequently after planting so that the soil stays moist to prevent herbs wilting. Typically water leafy herbs every 3 or 4 days until the herb is established. Herbs such as lavender prefer dryer conditions but should be water once per week after planting until their roots establish.
It is important to monitor your herbs and water more often after they are planted as this is the time when they are most susceptible to dying from drought, with leafy annual herbs at greater risk.
This is because the herb’s roots have not had a chance to establish in the soil so they cannot uptake water as efficiently. Therefore to compensate it is important to keep the soil moist so that the plant is hydrated and to mitigate transplant shock and wilting
For herbs such as basil, cilantro or mint water as frequently as require so that the soil is moist for the first 3 weeks. After 3 weeks or so the herb should have adjusted to its surroundings and the roots can draw upon moisture deeper in the soil so you can scale back the watering to once every 5-7 days.
For Mediterranean herbs it is important to water once a week for the first 4 weeks after planting.
This provides the herb with enough moisture so that it does not suffer drought stress and droop, yet minimizes the risk of root rot from overwatering. After 3 or 4 weeks water Mediterranean herbs once every 2 weeks for the first season.
After the first season the Mediterranean herb should be well established and could only require watering in times of drought or once every 2 weeks if planted in pots if there has been no significant rainfall.
To further mitigate the risk of root rot it is important to plant Mediterranean herbs in the right, well draining, sandy potting mix, read my article on the optimal potting mix for lavenders.
How Often to Water Herbs Indoors
Water indoor herbs once every 5-7 days with a generous soak so that the soil is consistently moist but not saturated. If the herb starts to wilt or droop increase the frequency of watering and move the herb temporarily away from direct sunlight whilst it recovers.
It is important to note that herbs can wilt as a result of too much moisture around the roots as well as dehydration.
Herbs most often wilt due to too much moisture around the roots because they are in pots without drainage holes in the base (causing water to collect around the roots rather then drain away) or due to trays and saucers (which prevents water from draining out the pot).
If your herbs are wilting and turning yellow these are the symptoms of root rot due to the soil being saturated (which excludes oxygen from the soil and suffocates the roots) rather then just consistently moist.
(If your herbs are turning yellow read my article how to revive dying herbs).
Ensure your herbs are planted in pots with drainage holes in the base to allow excess water to drain away from the roots and plant in good potting soil or compost as compost has the ability to retain moisture yet still have a porous structure that allows excess water to infiltrate so that the soil does not become boggy.
It is also worth noting that only leafy green annual herbs such as basil and cilantro grow well indoors (in a sunny window sill) whereas Mediterranean herbs require full sun and good airflow so should only be grown outdoors.
How Often to Water Herbs in Pots and Containers
Water potted Mediterranean herbs such as lavender and rosemary once every 2 weeks in the Spring and Summer if there has been no significant rainfall and do not water at all in the Winter as this promotes root rot. Water leafy annual herbs such as basil and cilantro once every 3-7 days.
Keep in mind that this advice is assuming the herbs are being planted in a pot that is around 12 inches across and ideally a clay, terracotta or ceramic pot rather then a metal or plastic pot or container.
Leafy annual herbs can survive in smaller pots but you may have to increase how often you water the plant to ensure that the soil is evenly moist as smaller pots dry out a lot quicker in the sun. At the hottest times of year it may even be necessary to water your annual herbs every day in pots and containers to prevent drought stress and wilting.
Test the potting soil to a finger to see if you need to water your annual herbs. If you can detect moisture in the top inch of the potting soil then its okay to delay watering for a day or so.
If the potting soil feels somewhat dry then give your herbs a good soak so that excess water trickles from the drainage holes in the base which indicates the water has infiltrated properly to reach the herbs roots.
At the height of Summer on the hottest and driest days your herbs may require watering almost every day. If your herbs are wilting despite the soil being moist then this is a survival strategy of herbs to decreases their leaves surface area to reduce transpiration and conserve water. The herbs usually recover when the temperature cools in the evening.
If this is happening to your potted annual herbs I recommend moving the pot to an area of morning sun followed by shade at midday and the afternoon. The allows your herbs to get plenty of sunshine so that they grow and stay healthy but also protects them from the blazing sun at the hottest part of the day as temperatures peak in the afternoon.
Mediterranean herbs prefer full sun and can tolerate drought so tend to thrive even at the hottest times of year. Do not water Mediterranean herbs more often as this just increases the risk of root rot.
How Often to Water Herbs Seeds and Seedlings
Water herbs seeds and seedlings twice per week so that the soil is evenly moist. Always water with a good soak so to encourage good root development. Allow the surface of the soil to dry to the touch slightly before watering again.
When watering herb seeds or seedlings it is always important to ensure that the soil is watered thoroughly as the prmotes the development of roots.
If the seedlings are watered too lightly then only the surface of the soil becomes moist which promotes shallow root development and leaves your seedlings more vulnerable to drought.
With a more generous watering the herb grows a more substantial and robust root system which is capable of up taking water deeper in the soil. This also increases the roots access to the nutrients it requires so that you have plentiful healthy herb leaves to harvest in the following few weeks.
Of course you should increase how often you water seedlings if the temperature increases significantly and ideally locate them in a cooler window sill, in an area of morning sun followed by afternoon shade to prevent heat stress and wilting.
The reason for letting the surface of the soil to dry slightly is because roots need access to oxygen for root respiration. If the soil is too moist then this can exclude oxygen from the soil around their small, developing root system which can cause them to suffocate.
Waiting to water when the soil is slightly dry to the touch ensures the soil is aerated so the roots can respire and the seedlings stay healthy, whilst always being hydrated.
- Water Mediterranean herbs such as lavender and rosemary every 2 weeks with a thorough watering during Spring and Summer. Always wait for the soil to dry out before watering again. Water leafy annual herbs such as basil and parsley every 3-7 days to ensure the soil is consistently moist.
- Water leafy annual herbs such as basil and cilantro once every 2-5 days after planting to ensure the soil is evenly moist to mitigate transplant shock. Water Mediterranean herbs such as thyme and sage once a week after planting for the first 4 weeks.
- Water indoor herbs such as parsley, basil and mint every 5-7 days to ensure the soil is evenly moist but not saturated. Increase watering to once every 3 days if the herbs start to wilt and move to a window with morning sun and shade in the afternoon whilst it recovers.
- Water Mediterranean herbs in pots such a lavender and rosemary every 2 weeks in Spring and Summer. Do not water in Winter as this increases the risk of root rot. Water annual herbs in pots every 3-7 days to ensure the soil is consistently moist and as often as every 2 days at the hottest times of year.
- Water herb seeds and seedlings once every 3 days ensuring the soil is evenly moist. Ensure that the surface of the soil dries to the touch slightly before watering again. If seedlings being to wilt move them to a cooler location with less sun before watering more often to mitigate heat stress.