Lavender is a Mediterranean herb that is very easy to propagate from a cutting. Here we look through the best practices and most effective steps to ensure a high rate of success with your propagated cuttings.
I have personally propagated lavender many times as it is my favourite plant and have learned from my experience, the best formula and the things to avoid.
The best way to propagate lavender is from a cutting in soil. This method has a far higher success rate then growing lavender from seed or growing cuttings in water.
Lavender is very difficult to grow from seed outside of its natural habitat as it requires a specific sequence of temperatures and environmental conditions that replicate those of their Mediterranean environment.
Growing lavender in water also has a much lower success rate in my experience as it is inherently as odds with the preferred growing conditions of lavender.
All lavender species are native to the Mediterranean (including ‘English lavender’) and are well adapted to tolerating hot and dry conditions. Lavender cuttings grown in water almost always suffer root rot and die back before growing.
Even if the lavender develops roots when propagated in water, the roots are often far delicate then the roots off cuttings grown in soil and the cutting often dies when the roots are damaged from transplanting it from water to soil.
The Best Time of Year to Propagate Lavender From Cuttings
The best time of year to take cuttings for propagation is in the early Spring. The temperature in Spring is cooler which means that whilst your cutting is in a vulnerable state, it does not have to contend with the hot and dry extremes of Summer which can cause it to dry out and die back before the roots develop.
An early Spring lavender cutting has more time to grow roots so it can sustain itself with water and nutrients before the high Summer temperatures and blazing sunshine.
May and June are usually the best months for taking cuttings for propagation as the threat of frost has usually passed, the temperatures are in the optimal range of being not too hot for the cuttings to dry up and not too cold that they die back due to cold stress.
With that said I have personally propagated lavender in the Summer and early Fall. In the early fall the soil has had all year to warm up which is good for root development.
Lavender cuttings taken in the early Fall can still have an impressive success rate as long as you provide some form of protection in the Winter if you are in a climate that experiences freezing temperatures.
Summer cuttings can also grow successfully, but there is a greater emphasis on providing a temporary humid environment to prevent the cuttings drying up. Additional shade at the hottest times of day is also necessary.
You can even take cuttings of flowering growth if that is your only option, but it is important to cut they flower off as the flower would require energy, nutrients and moisture, all of which are needed for the cutting to develop roots to survive.
Taking cuttings in the Winter is not recommended as the lavender is in a dormant phase, therefore the cuttings would grow roots too slowly to have any real propagation success.
How Long Do Propagated Lavender Cuttings Take to Root?
Lavender cuttings typically take 3 to 6 weeks or more to develop roots, but it depends on the time of year.
If the soil is warm and the lavender cutting is not having to contend with any additional stress such as high temperatures or harsh sunlight then cuttings take 3 weeks to root.
Whereas in cooler conditions the cuttings may take around 6 weeks to root.
You can tell when the lavender has develop roots when growing in soil when it starts to produce new growth, whether it be a longer stem, more leaves or even flowers developing.
New growth indicates the lavender has develop roots that are capable of up-taking the moisture and nutrients that are required for the plant to grow successfully.
Do I Need to Use Hormone Rooting Powder to Grow Lavender Cuttings?
It is not necessary to use hormone rooting powder for lavender cuttings to grow successfully. Lavender are still able to grow and develop roots just by planting them directly in the soil.
However in my experience, hormone rooting powder does increase the success rate for growing cuttings successfully.
I have personally conducted several small experiments over the years to see whether hormone rooting powder really does make a difference.
Every year I grow 10 cuttings with hormone rooting powder and 10 cuttings without. For the experiments I always took the cuttings in early June and treated them in exactly the same way.
On average, of the 3 years I recorded my results the cuttings with hormone rooting powder had a success rate of 7.6 out of 10 whereas the cuttings without the powder had an average success rate of 6 cuttings out of 10 growing successfully.
So the difference is not necessarily huge when averaged out but what I found was that one year was, it was particularly hot at the time of taking the cuttings and the cuttings with the hormone rooting powder were able to root quicker and therefore able to draw up moisture and more successfully contend with the hot Summer weather, whereas several of the other cuttings shrivelled in the heat.
The cuttings with hormone rooting powder were able to grow roots more quickly which stood the lavender plant in good standing to cope with Winter and they actually displayed more flowers as they had a head start over the cuttings without hormone rooting powder.
So on that basis I do recommend hormone rooting powder is it is relatively inexpensive and I had good results.
The Best Soil For Propagating Lavender From Cuttings
It is absolutely imperative to use the right potting mix for propagating lavender cuttings as lavender is very susceptible to root rot if planted in the wrong soil type.
In the native Mediterranean habitat lavender, grow in gritty or relatively sandy soil which has good drainage and low nutrients.
It is important to emulate these conditions for your lavender cuttings to prevent the risk of root rot. If you plant lavender in damp, water retaining compost, it is likely they all die back without growing properly.
To mimic the lavenders preferred soil type use around 30% horticultural sand or grit with 70% peat free compost.
This achieves the optimal balance of drainage and soil structure to facilitate the growth of the cutting.
Avoid using any compost that has added fertilizer as lavender prefers poor soil and excess fertilizer causes the lavender to grow weaker foliage (that is more susceptible to cold weather)at the expense of flowers.
Step 1 of Propagating Lavender – Choose the Right Pot and Potting Mix
Find a pot with a drainage hole in the base and fill it with at least 30% sand or grit and around 70% compost.
Here is a photo of my favourite pot to use for propagation. It is terracotta which is a porous material so the soil can dry out more evenly (whereas plastic pots are impermeable and can retain too much moisture).
I personally am using horticultural sand in the photos (available online and from garden centers). Horticultural sand has a larger particle size then normal sand for improved drainage and aeration.
Water the potting soil prior to placing the cuttings in the soil, so that the soil is evenly moist. Watering beforehand ensures the cuttings do not get washed out of place.
Step 2 – Choosing the Best Cuttings For Propagation
If possible select a lavender stem without flowers, but if it is all in flower, then no problem, select some healthy growth that is semi ripe and cut off the flower so the cutting can direct its energy to growing roots.
‘Semi ripe’ in this context just means selecting a stem that is roughly a month or so old with the top of the growth being greener and more flexible whereas lower down, the cutting has hardened off slightly and is more firm.
Cut a length of lavender that around 6 inches long with a sharp pair of pruners.
With sharp pruners, snip back any leaves that are in the bottom half of the cutting. The more leaves it has the more moisture it will lose, so removing the lower leaves whilst the cutting still has no roots increases its longevity and reduces the risk of drought stress.
It is of course important to leave some leaves on the cutting which provides the cutting with energy to grow the roots.
It is worth noting that the roots actually develop at the leaf node, so by removing the bottom leaves, the cutting as more nodes from which to grow roots. The leaf node is adaptable and capable of growing roots once it is in the soil.
Step 3 – Cover the Lower Portion of the Cuttings With Hormone Rooting Powder
Once you have stripped the lower potion of the cutting of leaves then dip it into the hormone rooting powder pot (if you have it) coating the bottom 2 inches or so of the cutting with powder.
The potting mix should be sufficiently light in texture that you can slot the bottom of your cutting into the soil at the edge of the pot.
The reason I recommend placing the cutting at the pots edge is because the side of the pot provides additional support to prevent the cutting from falling out of place.
Space your cuttings at least 3 inches apart to give each one enough space so it can access light.
Step 4 – I Recommend Taking At least 10 Cuttings
This is one of the biggest hacks for successfully propagating lavender…
Be generous with the amount of cuttings you use when propagating. One of the most common reasons why lavender cuttings die is because the soil holds too much moisture for this drought tolerant Mediterranean herb to tolerate.
If there are many cuttings in the soil then they all draw up moisture which means overall the compost does not stay damp for as long after watering which helps achieve the right balance of moisture for them to grow successfully and avoid root rot.
As lavender is drought resistant, root rot from damp, boggy soil is often a bigger threat to the cuttings survival then suffering from drought.
If you only have 1 or 2 cuttings in the whole pot then the compost dries out more slowly which increases the risk of root rot.
More cuttings also helps to spread the risk in the sense that some of them are likely to root even if you lose a few.
Step 5 – Use a Clear Plastic Bag to Prevent the Cuttings Drying out
Place a clear plastic bag over the top of the cuttings to help conserve moisture.
Whilst lavender does not like moisture as such, when it has just been cut you are essentially cutting off its means to uptake water, so it is at some risk of dying from drought.
The plastic bag over the top creates a slightly more humid micro climate to stop the cuttings drying out straight away.
If the weather is overcast with cooler temperatures then the threat of the cuttings drying out is not as severe and I recommend temporarily removing the transparent bag to avoid root rot and then placing the bag back over the pot when the weather is hot, dry and sunny.
By reactively taking the transparent bag on and off according to the conditions, you can achieve the delicate balance of ensuring the cuttings haven enough moisture for immediate survival without being too damp and developing root rot.
Step 6 – Where to Locate Your Lavender Cuttings
I locate the lavender cuttings in bright indirect light for the first 3 weeks or so until I start to see new growth.
Once new growth appears on your cutting then this is a sign that it has definitely developed roots at which point I relocate my lavender pot to an area of morning sun and protect the cuttings from the sun and midday heat in the afternoon.
The morning sun is less intense and the temperature is cooler which provides provides the cuttings with energy to photosynthesize and further develop its root system.
Afternoon sun is more intense and the temperature is usually hotter which can risk drying out the cuttings.
Step 7 – How to Water the Cuttings
The soil needs to be evenly moist after watering and then dry slightly before watering again. How often you specifically need to water depends on several factors such as temperatures, sun intensity and how well the potting soil retains moisture.
Therefore the best way to tell if it needs watering is by feeling the weight of the pot immediately after watering and then picking it up periodically to assess the weight as the soil dries. As soon as it feels noticeably lighter, it is a good idea to water the cuttings.
I personally also leave a little bit of space in the propagation pot to feel the soil to a fingers depth, so I can feel how moist the soil is, to get the best idea of when to water.
Use a rosette on your watering can that pours in a very fine, delicate stream as a big watering can without a rosette is likely to wash the soil away from your cuttings and ruin the propagation process.
For more information read my article, How to Water Lavender in Hot Weather.
Troubleshooting Lavender Propagation Problems
If your cuttings are wilting then give to the soil a water and place a bag over the top to temporarily increase the humidity. Some wilting is normal and to be expected on cuttings without developed roots.
Assess whether the wilting is due to lack of moisture (if the soil is moist and you using a bag for humidity then your likely okay) or whether it can be attributed to high temperatures and blazing sunshine, in which case provide some shade to alleviate the stress.
Keep in mind that too much water in the soil can also cause a drooping appearance, so if the cuttings are drooping despite the soil being well watered then try to ensure the soil stays evenly moist rather then boggy and move the cuttings to the shade if they are in the sun and the temperature is relatively high.
If some cuttings are dying, that is also to be expected. A 100% rate of propagation whilst possible is difficult to achieve even if you follow all the best practices.
Simply remove any cuttings that have died to prevent then from rotting and causing problems for the remaining cuttings.
How to Care for Propagated Lavender
The lavender cutting should develop its roots within 3-6 weeks, as which point a plastic bag is no longer necessary to retain humidity and is likely to do more harm then good once the plant is established.
The rooted cuttings are far less vulnerable to drought stress but it is still worth watering them once a week to ensure they do not dry out.
In my experience it is best to keep the lavender in the pot it has been propagated in for the first year to allow the roots to develop as much as possible without being disturbed.
If you live in a climate that experiences frost then it is best to keep your propagated lavender in either a cold frame (which is like a mini green house) or a green house to protect it from frost as immature lavender is more vulnerable to cold stress.
Sometimes propagated lavender actually produces flowers even in its first year to propagation, particularly if you take your cuttings in the early Spring.
It is actually best practice to snip any developing flower buds off, if your cutting has been propagated that year as this helps to redirect the lavenders energy to growing roots and establishing properly rather then the energy intensive process of displaying flowers.
Your lavender will look much better and be far more hardy the following year.
In the following Spring you can transplant your propagated lavender to its own pot (ensuring the soil is a mix of sand/grit and compost) and you should see flowers that year.
Of course the usual advice for lavender care applies, with lavender preferring full sun to produce the strongest fragrance, gritty soil with good drainage and only watering in times of drought.
Do not add any fertilizer to lavender as it has specifically adapted to growing in gritty soils with low fertility and good drainage. If you add fertilizer this can promote foliage growth at the expense of flowers and decrease the concentration of the essential oils that are responsible for their divine aroma.
For more information on caring for lavender once it has matured read my article, How to Care for Lavender in Pots.