The most suitable potting soil for woody Mediterranean herbs is a mixture of 1/3 sand or grit to 2/3 compost for the highest amounts of fertility, drainage, and soil structure that will ensure delicious herbs. Non-woody herbs like cilantro and basil prefer multi-purpose or garden compost that isn’t sand-based to increase soil moisture.
There is a distinction to be made between plants that are native to the Mediterranean region of Europe and non-woody plants with green stems is crucial when you are deciding on the best potting soil for your plants.
Mediterranean plants require a sharp drainage and less water around their roots due to their adaptation to dry climates. They can also be supported by the structure of their trees.
Non woody plants rely on pressure created by the vacuum created by transpiration of water from leaves (transpiration) which causes moisture in the soil of the potting plant to be drawn upwards through the roots, which keeps their green, leafy non woody structure.
Read on to learn how to make the perfect herb potting soil and what soil amendments you should stay clear of to get the greatest flavor when you plant plants in containers…
Best Soil for Mediterranean Herbs
Many of the most sought-after herbs for their flavor and aroma come in regions in the Mediterranean area of Europe in countries like Span, Italy and Greece where they flourish in the wild and are cultivated for commercial purposes.
To grow delicious Mediterranean plants, it is essential that you recreate soil characteristics of their original environment . This can be done by amending your potting soil to ensure that it is reminiscent of Mediterranean soil. It is a well-draining sandy soil which is lacking in nutrition and doesn’t retain moisture.
The following herbs are all found from the Mediterranean region, and all require the same mix of potting soil:
The most suitable potting soil for Mediterranean plants like rosemary and lavender is made up of 70% peat-free multi-purpose compost, 30percent horticultural sand, and grit. A compost and grit potting mix mimics Mediterranean herb soils that have excellent drainage, moderate fertility, and an aerated soil structure.
A sandy, grittier potter’s soil is similar to the prefer sandy soils, which is essential to prevent root rot and ensure that your plants have the finest flavor and scent.
Sand and grit offer vital drainage properties and don’t provide many nutrients to soil, or hold in moisture that can increase the strength of the flavor and aroma of your plants.
Check out this short video and discover how simple it is to make the ideal soil mixture for Mediterranean herbaceous plants (such as lavender). )…
Mediterranean herbs are specially designed to work in soils with lower fertility and, therefore, if planted in compost rich in nutrients with fertilizer added, their distinct flavor and aroma isn’t as strong, and may be more susceptible to disease and pests.
The excess nitrogen in nutrient-rich soil encourages excessive foliage and reduces the amount of the essential oils within the leaf that provide the herb’s flavor and aroma, and hinders the herb from flowering.
In soils with a high fertility Mediterranean herbs don’t taste as strong , so it’s best to recreate the natural conditions of their growth with less fertile potting soil and a good drainage system so that you can experience the distinct scent and flavor of your herb when cooking.
(Read my blog post on selecting the most suitable containers and pots to grow lavender in.).
Avoid These Potting Soils When Growing Mediterranean Herbs
- Any soil mix that contains manure (too too much nitrogen).
- Commercial soil mixes that contain wetting agents that help retain the moisture or to add nutrients.
- Unamended soil that is free of inorganic matter (sand or perlite, or grit).
- Ericaceous compost.
It is crucial to emphasize that Mediterranean plants prefer soils with lower nutrients which drain quickly and don’t hold on to water.
If your potting soil contains an excessive amount of nitrogen, your plants will are likely to grow sloppy, hanging over and are more susceptible to fungal diseases So, always choose multi-purpose compost for your plants instead of manure or compost with added nutrients since they are typically rich in nitrogen, which can diminish the flavor of your herbs.
All Mediterranean plants thrive in pots with adequate drainage. They are specifically designed to thrive in environments with less water, and have thinner needle-like leaves that restrict the transpiration (water loss) of the leaves.
The ability to thrive in more dry climates can make the plant more prone to root when they are in a potting mix that remains wet for long periods of time this is the reason why adding grit or sand is crucial.
(Read my article on on how to bring back dying plants).
In areas with high rainfall, I suggest increasing the amount of grit or sand to 50 percent (with 50% of multipurpose compost) to combat the greater levels of rainfall that can cause humid conditions..
A little more sand, or even grit is better than is not enough in the soil used for potting of Mediterranean plants due to their susceptibility to excessive moisture and preferring dry conditions.
Mediterranean plants have evolved to thrive naturally in soils that are typically pH 7, moderately alkaline or neutral pH 7.1-8 however they are able to take a moderate acidity of pH 6.5.
Multipurpose compost of good quality typically has a pH of 7. It is the ideal pot soil suitable for all Mediterranean plants.
It is nevertheless important to stay clear of the ericaceous (acidic) soil, which typically has a pH of 6. This is too acidic for Mediterranean plants, which stops the roots from absorbing nutrients, and could cause death to the plant.
Best Potting Soil for Basil, Cilantro, Mint, Chives and Parsley
While herbs like basil and cilantro (parsley), mint, fennel, dill , and chives are used in Mediterranean cuisine but they aren’t indigenous to the Mediterranean region, and thus need different conditions for soil, in contrast to the herbaceous Mediterranean herbs.
Herbs that don’t originate from the dry and hot Mediterranean climate need potting soil that has more capacity to hold water for the roots to absorb the required amount.
The most suitable potting soil for herbs like cilantro, mint and basil is a high-quality multipurpose compost, as it holds in the moisture needed to keep it from wilting, yet lets excess water be drained away. Multipurpose compost also offers the perfect combination of nutrients and soil structure to give a rich flavor and allows the roots to grow.
Garden compost that is well rotted and composed of garden waste and food scraps (such in vegetable peelings) can also be used to plant the majority of non Mediterranean plants due to its attractive structure and capacity to retain moisture.
While potting compost retains moisture , it also has a friable structure that permits excess water to flow easily away, rather than accumulating around the roots and trigger root decay.
(Read my article on what is the best time should you water your the herbs).
Multipurpose compost (available at garden centers or on the internet) is not required to be amended with additional substances when you are cultivating herbs like cilantro, basil (parsley) mint, basil or chives. Adding inorganic materials (such as grit or sand) can cause the soil to drain faster than it is required, and can cause the herbs to drop.
The capacity to retain moisture of the soil used for potting is the main reason behind the different preferences of potting soil for plants that come from the Mediterranean that tend to be wooden in their structure. However, other herbs like basil depend on a continuous supply of water at the roots and a consistent flow of the leaves to keep the pressure of tugor that allows the plants to remain upright in absence of a woody structure that can help them.
Potting Soil to Avoid for Basil, Cilantro, Mint, Chives and Parsley
The majority of non Mediterranean plants aren’t very fussy in regards to soil for potting, but there are certain soil amendments you need to be wary of.
- Do not plant herbs in potting soils that have been altered by adding nutrients.
- Avoid soil amendments like manure or coffee grounds because of their nitrogen content.
- Any soil that is amended with the highest proportion of either sand, or even grit.
The reason that herbs like basil have a taste and smell that is so strong and distinct is due to the amount of essential oils within the leaves.
If you plant your herbs in potting soils that are rich in nutrients, whether it’s from prepared soils for potting or amendments like manure, this could encourage growth of the foliage, however it reduces the amount in essential oils which decreases the intensity of the flavor and aroma of your herbs.
Do not add coffee grounds into the soil for potting when you are cultivating herbs. Coffee grounds are rich in nitrogen, which can diminish the aroma and taste of your plants and cause an excessive amount of drooping in the foliage, which makes the plants more susceptible to disease and pests.
The leafy plants that do not have the woody structure also depend on constant sources of moisture to maintain the structure of their plants and keep the plants from falling down.
Sand or grit could cause soil to drain too fast and result in plants that turn to yellow and die because of drought stress.
(Read my article on selecting the most suitable pots for your herbs).
- The most suitable potting soil for Mediterranean plants is a potting mix consisting of two thirds compost and one third horticultural sand , or grit. The addition of grit or sand mimics the ideal soil conditions of the herb’s natural soil type that has excellent drainage, moderate to low fertility, and an aerated soil structure.
- The most suitable potting soil for basil is a high-quality multi-purpose compost that retains moisture but also offers excellent drainage and moderate fertile, and an airy structure that is suitable to help the growth of the basil’s root system. Potting soil that is too high in nutrients can reduce the potency of basil’s aroma and flavor.
- Don’t add coffee grounds to the potting soil of herbs because the nitrogen content encourages growth of the foliage however it reduces the aroma and flavor of the herb. Coffee grounds that are added to potting soil may cause the herbs to shrink and weaken the plants and make them more susceptible to diseases and pests.
- The most suitable potting soil to grow lavender in is a potting mix consisting of 1/3 horticultural sand, or grit, 2/3’s multi-purpose compost, as it mimics the soil conditions that are typical of the lavender’s Mediterranean habitat. The proportion of sand and grit will ensure that the soil drains effectively to ensure the proper balance of nutrients and moisture and prevent root decay.