Lavenders are a relatively low maintenance plant, however there are some winter care best practices that you need to be aware of over winter to ensure you lavender survives:
- Lavenders need dry roots. If your soil does not drain quickly then you will need to amend the soil with sand or grit as cold winter soil will retain moisture for longer.
- Reduce the frequency of watering lavenders in winter. Established outdoor lavenders will not need watering over winter. Indoor lavenders need watering once every 4-6 weeks.
- English Lavenders are cold hardy and can be left outside over winter. Non English lavenders will only survive winter in mild climates and need to be transferred into pots and brought inside over winter.
- Prepare your lavender for winter by pruning them into a mound shape that resists winter weather and tidy away leaves.
Read on to learn exactly how to implement these steps to ensure that your lavender is care for over winter so that it can provide a beautiful bloom with strong aromas in the following growing season…
Prepare Lavenders for winter
To prepare you lavenders for winter the two most important things you can do are:
- Tidy away fallen leaves that have accumulated around the lavender
- Prune the lavender into a dense, robust mound shape as this will more effectively resist the effects of Winter weather.
Fallen leaves can act as a useful mulch for some plants but lavenders prefer soil drains well and does not hold onto excess moisture. This is because lavenders are native the the Mediterranean region of Europe where they thrive in sandy soils that are relatively low in fertility.
Leaves have an exceptional capacity to hold onto water, which will create unfavourable conditions that could lead to the fungal disease root rot, which commonly occurs in damp soils.
So at the end of Fall, make sure that you get a rake (or use a leaf blower) out and clear all decaying organic matter from around your lavenders and place it on your compost heap.
At this time of year you can lay some sand or gravel down to act as a mulch to suppress weeds. The sand in particular will wash into the soil over time and improve the soils drainage by creating a more porous structure.
Pruning Lavenders Before Winter
Lavenders should be pruned every year as this will slow down the formation of woody growth, increase the longevity maintain an attractive shape and stimulate greater flower production.
(If your lavender has a lot of woody growth, then read my guide on how to deal with it).
The main pruning should be done at the start of spring to really dictate the lavenders shape and appearance. However you should also perform a light pruning of your lavender plants in the late summer/early fall to prepare you lavender for the coming winter.
The goal with lavender pruning should always be to form a nice, dense mound shaped shrub as this is considered most attractive and it will prevent winter damage.
To prune your lavender for winter you should cut spent flower stems back and tidy up the appearance, round off the lavender nicely.
The golden rule of lavender pruning is to never cut back to the woody material as the wood does not rejuvenate and the wood is the weakest least resilient part of the plant.
At this time of year you should not be taking much foliage off the lavender. The most you should cut back is a third of the green growth, the most important factor is to shape the lavender into a mound so it is more robust.
A mound shape will prevent and deflect snow, ice or excess water from getting inside the lavender and harming the more vulnerable woody base of the lavender plant.
Watering Lavenders over Winter
Lavenders enter a state of winter dormancy and do not require much water at all over winter. Lavenders are also a drought tolerant shrub so watering over winter is very low maintenance.
Established lavenders will not need any additional water over winter. The problem with lavenders is usually with too much water over winter thanks to the higher winter rainfall in most climates.
Lavenders in their first year of growth may benefit from water once every 4-6 weeks in winter if there has been no significant rainfall, but they will more then likely receive sufficient water over winter without watering thanks to lower evaporation rate in cold weather.
It may be necessary to bring potted, non English lavenders indoors over winter to protect them from frosts. In these circumstances the lavender will require a moderate amount of water over winter to stop it from drying out completely.
(Read, Watering Lavender in Pots for watering advice all year round.)
This should be done once every 4-6 weeks, however if the soil feels remotely damp to the touch (when tested to fingers depth) then you should forgo watering for now.
Caring for English Lavenders over Winter
The English Species of lavender is the only species that can tolerate the winter and frosts of a temperate climate.
This hardy lavender species can grow in zone 5 in the USA with the variety Hidcote Superior able to survive the winter with temperatures as low as -30 °C (-20 °F)!
Whilst English species of lavender can tolerate the cold and frost it will be susceptible to the effects of cold wet soils that are problematic in winter.
Despite the name “English” Lavender, all lavenders originate from the Mediterranean region of southern Europe and therefore require similar soil conditions, such as low fertility and good drainage.
Soil that drains quickly and does not hold onto moisture is even more important in the winter to avoid the effects of root rot (lavender roots prefer to be dry).
To ensure sharp drainage, soils should be amended with sand or gravel to a depth of 18 inches before planting lavenders.
If your lavenders are already planted in the ground you can simply ease the plant out carefully with a fork, not a shovel (to avoid damaging the roots) and mix in some sand or gravel, aiming for proportions of around 30-50% sand to 50-70% compost. The more moist the soil is naturally, more sand you should use when amending the soil.
Amending the soil will ensure lavender roots are not stuck in cold damp soil that drains too slowly.
Caring for Non English Lavenders over Winter
The Spanish, French and Italian species of lavender are different from the English varieties in that they are not cold hardy and need to live in climates that have mild winters, that do not reach freezing.
Some hybrids and varieties of non English lavenders are more cold tolerant then others but most will die if exposed to heavy frosts.
So if you are in a climate that receives frosts in winter then you should opt for a variety of the English species.
If you have non English species of lavender planted in your garden that you are concerned about because of cold weather then you can transplant the lavender into a pot and bring it indoors, (placed in a sunny window) or heated green house over winter.
Lavender of all species grow very well in pots as they tend provide the ideal drainage conditions.
Alternatively if you live in a climate with mild winters and there is an unseasonable frost expected you can use a cloche which are excellent at insulating plants or you can improvise and use a blanket or old duvet to throw over the plant to keep out harmful frosts as a short term, infrequently required strategy.
How to Care for Indoor Lavenders over Winter
Caring for indoor lavenders over winter is very easy. These low maintenance plants do not need much care and attention if they are indoors as they will be protected from the cold.
Avoid placing indoor lavenders in rooms that potentially have higher humidity, such as the bathroom and kitchen. Give the lavender a generous amount of space to allow some air flow through the foliage.
You may need to water your indoor lavender once or twice over the winter to ensure it does not dry out as obviously it will not be able to attain water naturally, like outdoor lavenders will.
For more information and best practices, check out my guide on how to care for indoor lavender.
Caring for Potted Lavenders over Winter
Potted lavenders are more vulnerable to the cold and frosts as there root system is effectively above ground and not insulated to the same extent that planted lavenders are.
Therefore if you are expecting a heavy frosts or particularly cold temperatures it is a good idea to take them inside for a few nights until the cold snap has passed.
This is of course particularly true for the Spanish, French and Italian species which do not tolerate frosts, hence why planting these varieties of lavenders in pots is a good idea, unless you live in a particularly warm climate with mild winters.
The same care practices apply to potted lavenders as with any others, such as good soil drainage that has been amended with sand, water very infrequently if indoors and not at all if outdoors during the winter dormancy and place them in a sunniest location in your house or garden.
Read Can Lavenders Grow in Pots? for advice on caring for potted lavenders all year round.
- Prepare lavenders for winter by pruning them late summer or early fall, into a dense mound shape to increase resistance from hostile winter weather and to deflect snow.
- Clear away fallen leaves and decaying organic matter from around the lavenders as this will only encourage the disease root rot.
- Established outdoor lavenders do not require any water over winter as they are drought tolerant. Too much water will harm the plant and potentially lead to root rot. Indoor lavender may require infrequent watering in winter; no more then once every 4-6 weeks.
- Make sure that the soil drains quickly. Wet, cold winter soils can cause root rot and kill lavenders. Amend the soil with plenty of sand or gravel to improve the soil structure and increase the rate of infiltration so that the lavenders roots stay relatively dry.
- English Lavenders are the only species that can tolerate frosts and cold weather, through winter.
- Spanish, French and Italian lavender are not cold hardy and will most likely die in frosts. If you live in a cold climate then you should transplant these lavenders into pots, take them indoors and place them in a sunny window before returning them to the garden the following spring. Alternatively if you live in a mild climate, then you can keep them outside all year round and use a cloche to protect them against the occasional cold snap.
- Indoor lavender require occasional watering over winter. Once every 4-6 weeks will be enough as lavenders enter a state of dormancy over winter and lavenders are drought hardy.