Clay and terracotta pots measuring at least 12 inches across are the best of pots for growing rosemary. Clay and terracotta are porous which allows the soil to dry after watering, they do not heat up as quickly in the sun compared to plastic or metal pots and provide more protection from frost in Winter.
Rosemary is a Mediterranean herb that has adapted to resist drought and prefers the soil to dry out somewhat between bouts of watering, which is why a porous material such as clay or terracotta is best, as it allows the soil to dry out efficiently after rainfall, whereas plastic pots are not breathable and can retain too much moisture for the rosemary to tolerate.
Keep reading to learn which pots and containers are the best for growing rosemary and how to avoid the most common mistakes when growing potted rosemary…
Best Pot Size for Growing Rosemary
Rosemary can come in a variety of sizes with some varieties growing as much as 2 or 3 feet across (such as ‘Tuscan blue’) whereas some varieties stay much more compact with annual pruning.
However I recommend that you plant your rosemary in a pot that is at least 12 inches wide with the same proportional depth even if you have a smaller variety of rosemary or if the rosemary is at an immature stage of growth.
It is important to plant rosemary in a pot or container that is at least 12 inches because the pot needs to have enough capacity to hold enough soil for the rosemary’s roots to stay insulated in the Winter and so that the pot does not dry out too quickly in the blazing sunshine in the middle of Summer.
A 12 inch pot also has enough room for the rosemary’s roots to develop so it can access the moisture and nutrients it requires to grow and stay healthy.
Rosemary of all type grow very well in pots and as pots have more favorable drainage conditions compared with garden boarders and flower beds which is important because rosemary are Mediterranean plants which are adapted to well draining conditions which helps to avoid root rot.
As rosemary is a Mediterranean plant, it grows, smells, tastes and flowers the best when it is full sun.
However full sun can drastically increase the rate at which pots dry out on the hottest days, which is why having a larger pot with a good capacity for soil is so important, as pots that are smaller then 12 inches can dry out so quickly that the rosemary roots do not have enough chance to draw up the moisture they need.
It is also worth considering that pots essentially raise the rosemary’s root system above ground which can expose the roots to cold temperatures in Winter.
The roots of rosemary are the most cold sensitive part of the plant. Ordinarily the surrounding soil acts as insulation from the cold to maintain a temperature during Winter that the roots can tolerate.
If the pot is too small then it does not contain enough soil to properly insulate the roots from the worst of the cold which can cause your rosemary to die back in Winter.
A larger pot has enough soil to insulate the roots and protect them from frost in climates with colder Winters so that they survive and flower well the following year.
(Read my article, best soil for rosemary in pots).
Best Material Rosemary Pots
Rosemary are hardy plants when established and growing in the right conditions and they are able to grow in pots made from any material by there are some types of pots that are more favorable for growing rosemary then other.
Rosemary plants are capable of growing in metal, plastic, clay, terracotta and ceramic style pots.
However metal pots (as show in the photo) and to some extent thin plastic pots have a tendency to heat up more quickly in the sun as the material conducts all the heat efficiently from the sun.
If the pot heats up too much then this can stress the roots and cause water to evaporate too quickly from the soil causing it to bake hard and prevent the rosemary’s roots from drawing up any moisture.
Rosemary is adapted to tolerating drought conditions as it comes from the Mediterranean region of Europe where it tolerates hot and dry Summers, so they may be able to grow in metal or plastic pots without a problem in the right climate and if the pot is big enough so that it does not dry out as much in the blazing sunshine.
However if the pot is conducting heat all day, then you have to be more diligent with the watering to ensure your rosemary does not suffer drought stress. Conversely rosemary prefers dryer soil conditions so watering too frequently can cause root root which makes getting the balance of moisture for rosemary difficult in metal and plastic pots.
(Read my article, on how often to water rosemary).
My personal recommendation for the best pots for growing rosemary are terracotta or glazed clay pots.
These pots are more hard wearing to the elements then plastic or metal pots yet they are also porous and breathable which allows damp soil to dry somewhat after a bout of heavy rainfall which really helps your rosemary avoid root rot as root rot is the most common problem when growing rosemary.
Clay and terracotta pots are the best choice for growing rosemary. Clay and terracotta pots are made a lot thicker then metal and plastic pots or plants. This means they do not heat up as quickly in the Summer or bake the soil and resist frost damage to the rosemary’s roots in Winter.
Whilst clay and terracotta are the best pots for rosemary, it is important to consider they can get very heavy compared to plastic and metal pots, particularly with the weight of potting soil and the plant itself.
Some rosemary varieties are not cold hardy and may have to be brought indoors over Winter to protect it from frost damage, in climates with cold Winters.
Moving your pots indoors every can be difficult so a lighter plastic pot, preferably in a light color (so it reflects light rather then absorbs light and heat), may be a better option.
(Read my article, how to care for rosemary in pots).
Good Drainage is Key for Rosemary Pots and Containers
Which ever style of pot or container you choose for your rosemary the most important feature is that, it has to have drainage holes in the base to allow excess water to escape after watering.
If the pot does not have drainage holes then water collects in the bottom and the soil around the root of the rosemary plant become saturated which promotes the conditions for root rot causing the rosemary to turn yellow, brown or black and die back.
(Read my article, how to revive a dying rosemary plant).
It is important to emphasize that drainage holes should also be kept clear to allow water to escape easily away from the roots.
Soil can become compacted in pots over time so the best way to ensure that the drainage holes stay clear is to use a 1 inch layer of gravel on the bottom of the pot before adding potting soil.
The gravel maintains a porous, aerated structure at the base of the pot to allow water to drain away easily as soil compacted at the base can cause the water to drain slowly and cause boggy conditions.
It is also best practice to place potted rosemary on little ornamental pot ‘feet’ or stands so that the pot is slightly elevate off the ground.
This prevents water from collecting underneath your pot if it is placed on a patio, which can cause the soil at the bottom of the pot to stay too damp as rosemary requires the soil to dry out between bouts of watering.
Avoid this Common Mistake!
A classic mistake I see when people have potted rosemary is that they choose the right type of pot without good drainage in the base but place the pot on a tray to prevent water spilling on their patio of watering the rosemary.
Rosemary originates in the Mediterranean region of Europe and requires dryer soil conditions then most plants, so if the pot is on a tray with water around the base, it is contrary to the conditions rosemary prefer and can cause root rot.
Key Takeaways:
- Clay and terracotta pots are the best pots for growing rosemary. Clay and terracotta pots are more breathable then plastic and metal pots allowing the soil to dry out more efficiently, they do not heat up too quickly in the sun and resist frost damaging the rosemary’s roots in Winter.
- Clay and terracotta pots that measure 12 inches across have the capacity to hold enough soil for the rosemary root system to develop and provide enough insulation to protect the rosemary’s roots for the cold.
- Always plant rosemary in pots with drainage holes in the base to allow excess water to drain away from the roots to prevent root rot.
- Avoid placing your rosemary on a tray as this collects water and the soil stays boggy causing root rot. It is best practice to place your pot on stands to allow for good drainage and prevent root rot.