How Often to Water Herbs

Are you new to herb gardening and struggling to understand how often your herbs should be watered? If so, don’t worry; here at Gardener Report, we understand your struggle!

Some herbs require watering more often than others. Some hate dry soil, and others thrive in dry conditions… It’s confusing, right? In this article we are going to talk about the nuances of when and how much to water different herbs.

I’ll give you all the tips and insights gained from my personal experience of growing almost every single type of herb for many years!

Here is the bottom line…

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 we nee to acknowledge when it comes to how often to water different types of herbs is whether they are perennial herbs originating 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, we only need to water these once every 2 weeks at the most (once they have been established).

Leafy annual herbs require the soil to be consistently moist (but not saturated), so they should be watered as often as required to keep the soil moist (which varies according to the time of year).

For those of you in a rush I create a table to use as a quick reference guide for how often to water herbs at different times and conditions…

It is important to note that this table is a guide, and several variables, such as the size of the pot, temperature, and the hours and intensity of the sun, can affect how often herbs are watered.

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

So, our Mediterranean herbs are the most fussy when it comes to watering…

Water your 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.

When watering our Mediterranean herbs, we need to get into the Mediterranean mindset and understand how they grow in their native climate!

Mediterranean herbs refer 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:

• Lavender
• Rosemary
• Sage
• Thyme
• Oregano

All these herbs thrive in dryer conditions and, therefore, should be watered significantly less often than leafy annual herbs.

We need to remember that annual herbs are very forgiving when it comes to overwatering, whereas Mediterranean herbs are less so…

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, they are particularly susceptible to root rot therefore you must try replicate their natural conditions by watering them less often than other plants.

After some trial and error, I discovered that the optimal watering frequency for Mediterranean herbs is to 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 than 12 inches across.

But I have to say generic advice on how often you should water herbs can be misleading as there are some many variables that affect how long the soil stays damp for.

However, there is a way I can tell whether any Mediterranean herb needs watering regardless of climate. How do I do this?

I present to you the finger test! What I do is push my finger into the soil to see whether I can detect moisture. If the soil feels damp, then delay watering until it feels mostly dry. When it’s dry, give it a really good soak. The soil also sticks to your finger if it is damp and less so if it is dry.

I have also used a moisture meter for these purposes but to be honest I fin they are often not precise enough and my finger does a better jobs of assessing the soils moisture.

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.

However, you should only water your Mediterranean herbs in Spring and summer during active growth and avoid the common mistake of watering in Fall and Winter.

Mediterranean herbs attain all the water they 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.

What I have found is that Mediterranean herbs that are planted in raised beds or as hedges in garden boarders do not require any watering at all once they have been established after the first year as they are capable of thriving in the hot and dry Summers of Southern Europe without any need for watering.

How Often to Water Leafy Annual Herbs

As we discussed, it is difficult to give generic advice on how often you water your herbs as there are too many variables to take into account.

But typically I water my leafy 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, I water my annual herbs as often as every other day, particularly if they are in small pots outdoors.

Types of popular annual herbs include:

• Basil
• Cilantro
• Chives
• Mint
• Dill
• Fennel
• Parsley

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, we need our annual herbs to grow in consistently moist soil, which should be watered more often than Mediterranean herbs.

With Mediterranean 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) I personally have not had an issue with overwatering annual herbs at any point apart from once when the drainage holes in the base of the pot were blocked.

There are several factors such as the 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 your herbs are planted in organic, rich compost or potting soils that drain well, are planted in a large enough pot (12 inches across and deep), are placed in partial shade, and then watering once every 4-7 days is usually sufficient.

I personally only have to adjust my freuncy of watering during heat waves in the middle of Summer. I remember a few years ago I had to water nearly every day as the temperature was so high and the sun was so intense.

My remedy to this was just hade the herbs from the sun in the afternoon and they soon perked up!

Adjust how often you water these herbs if they start to show signs of drought stress, such as leaves curling or wilting and give them a really good soak so that the water can infilrtate the soil and reach the roots.

I sometimes see people make the mistake of watering too lightly and only the top inch or so of the soil becomes moist and it can be relatively dry around the roots of your herbs so always watering thoroughly.

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 than a lack of moisture) and return to normal once temperatures have cooled in the evening.

As we discussed earlier, with the Mediterranean herbs, I test the soil’s moisture to a finger’s depth to check whether my herbs have enough moisture.

Typically I water when the surface of the soil feels but there is still some moisture to a fingers depth. This is a good way to establish the optimal watering frequency for your herbs in your garden according to the conditions rather than a generic schedule.

How Often to Water Herbs After Planting

So, we need to be a bit more diligent when watering our herbs straight after planting…

Water annual herbs such as basil frequently after planting so that the soil stays moist to prevent herb wilting. Typically, I water my leafy herbs every 3 or 4 days until the herb is established. Herbs such as lavender prefer dryer conditions but should be watered once per week after planting until their roots are established.

Of course, this advice is dependent on what time of year you are planting your herbs.

I personally plant mine in early Spring (March or April) as you can water these herbs every 3 or 4 days without the newly planted herbs contending with the higher temperatures of Summer. If you are planting your a little later into the summer, then you may have to water them every day.

But a better tactic is to plant them in a nice big pot, monitor the soil’s moisture and watering accordingly, and shade them in the afternoon whilst they are established.

We need to monitor our 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 required so that the soil is moist for the first 3 weeks.

After 3 weeks or so, the herb should have adjusted to the soil, and the roots can draw upon moisture deeper in the soil, so you can scale back the watering to once every 3-7 days (depending on the weather).

We need a different approach for our 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, my Mediterranean herbs are always well established and 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

I love a grow some herbs on a window sill in full sun as this distance from ‘field to fork’ is literally just a few feet! It is the freshest way to grow and harvest herbs.

What I’ve found works is to 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.

We need to remember that our herbs can wilt as a result of too much moisture around the roots as well as dehydration.

Whenever I see herbs wilt indoors, it is 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 than drain away) or due to trays and saucers (which prevent 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 than just consistently moist.

(If your herbs are turning yellow, read my article on how to revive dying herbs).

Therefore, it is crucial to 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 can 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 (on a sunny window sill) whereas Mediterranean herbs require full sun and good airflow so should only be grown outdoors.

I often recommend growing herbs indoors for beginners because you can easily monitor the soil’s moisture and gain confidence with watering.

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 assumes the herbs are being planted in a pot that is around 12 inches across and, ideally, a clay, terracotta, or ceramic pot rather than 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 the 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 it’s 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 herb’s 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 decrease their leaf’s 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. This 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 the 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

I recommend watering herbs seeds and seedlings twice per week so that the soil is evenly moist. Always water with a good soak to encourage good root development and allow the surface of the soil to dry to the touch slightly before watering again.

I must emphasize how important this is! If you water well and deeply when the roots are developing, the roots are encouraged to grow further down into the soil to tap into the moisture reserves. This more extensive root system has 2 advantages:

1. Your herbs are going to be WAY more resistant to drought if they have a more extensive root system.
2. Deeper, more extensive roots mean your herbs have more access to nutrients, so you are going to have a better harvest!

I’ve made the mistake of watering the soil too lightly, which results in only the surface of the soil becoming moist, which promotes shallow root development and leaves your seedlings more vulnerable to drought.

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 dry slightly is that 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.

So I just tap the surface of the soil to assess when they need watering.

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.

To be honest, the most difficult part of watering herb seeds and seedlings is actually watering them without washing away the tiny seeds or the compost in which they are planted. I did my research and conducted a few experiments to find the best method for watering my herbs’ seeds and developing seedlings.

My Method for watering Herb Seeds and Seedlings

So I had trouble with watering as my watering can would pour with a stream that was too powerful and washed the soil away around the herbs, even when I tried to trickle it gently. We nee to remember that it is much better to give the soil a deep soak.

So how did I do it?

I placed my seed trays and pots in a wheelbarrow, which was filled with a few inches of water, and left it to soak for 30 minutes or so. The compost had drawn up the moisture through the drainage hole in the base, and the potting medium was optimally evenly moistened.

Bottom watering like this also means the bottom of the soil is particularly moist, which entices the roots of your seeds to grow nice and deep, so your herbs are super drought-resistant!

The other way I have done it is by using the smallest watering can I can find with a rosette that creates the most gentle of streams to water the herb seeds without washing the soil away.

While this method was effective and got the job done, I found it tedious and slow! I much prefer leaving my pots and tray in a wheelbarrow or tub with water, and then I can do other jobs around the garden while they soak up the water!

However, we must remember to let our seed trays and pots drain well after using this method.

Key Takeaways:

• 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 as 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 begin to wilt, move them to a cooler location with less sun before watering more often to mitigate heat stress.