How to Grow Lavender

This article is part of our “How to Grow Herbs” series. If you would like to learn more about how to work with this plant after you harvest it, please refer to our Herbal Aromatherapy Certification Program™ here. I also have a full sample lesson on lavenders from that program available for you to read here.

There are at least 40 known species of lavender with an ever-growing count of over 400 cultivated varieties. Some of my favorite varieties have pink and white buds, but most of them feature vibrant shades of violet.

Hardiness and plant size varies depending on the species, so you will need to know what kind of lavender you are growing to space them properly and to ensure that they will survive the winters where you live. Some species are quite hardy (usually down to a zone 5 or 6) whilst others will not winter over in areas that have winter frosts and need to be protected during the cold months.

Growing from Seed

Lavender plants can be grown from seed or propagated through cuttings. They cross-pollinate freely, so seed-grown lavender will not produce seedlings that are true to the variety of the parent plant unless you isolate the flowers to prevent cross-pollination and hand pollinate them with the same variety of lavender.

If you were to plant a packet of lavender seeds without ensuring that the seeds therein were not cross-pollinated, you would end up with hundreds of little lavender plants that could all look or smell a bit different from each other. Because of this, if you want a uniform field of lavender or if you want to grow a specific variety of lavender, you will need to purchase rooted cuttings of that variety rather than starting from seed. There are lavender growers who sell trays of rooted plugs to gardeners and farmers who wish to grow a uniform patch or field of plants. These plug trays can be a great way to source plants if you are starting a lavender area in your garden and want to grow more than a handful of plants of the same variety.

To sow lavender seeds, you will want to scatter them on the surface of your soil (I prefer to start them in trays), lightly cover them with soil, and water them in gently. Keep the soil evenly moist until the seedlings have a few sets of true leaves, then you can transplant the seedlings into individual pots to grow a little more before you move them out into the garden.

Soil is Key

When you grow lavender, it is important to give it soil conditions that will keep the plants happy. They hate having “wet feet,” which is a gardener’s way of describing of soggy roots. The soil needs to drain well and not be in an area that gets boggy or that holds and collects water during the rainy season. If you have heavier soil or a lot of rain in your area, you might find it better to plant your lavender on a hillside or slope to improve drainage. A south-facing slope is ideal. When this is not possible, consider amending your soil with organic matter and perhaps a bit of sand to lighten it up a bit and improve drainage. Raised beds can also be used to control soil quality and drainage.

Sun Exposure

Lavender prefers full sun, though I have found that the L. stoechas varieties can tolerate partial sun / shade. We have a few volunteer plants that grew from seed near the base of a maple tree in our garden (we left them alone so we could observe them) and they do quite well there with morning sun and afternoon shade.

Growth Progression

In the first year after planting, lavender plants stay fairly small and will produce only a token amount of flower spikes, if any (plants reproduced via cuttings will usually produce a few flower spikes, but seed-grown first year plants may not). Many growers recommend cutting off the flower spikes this first year to give the plants a chance to channel all their focus toward establishing healthy roots.

In their second year of growth, lavender plants expand in size and produce a slightly larger harvest but have still not yet reached their mature size. In their third year, they should reach full size if they have been given enough space and are otherwise healthy.

Pruning

Each year, you will want to prune your plants to keep them well-shaped in that classic lavender dome or tuft. For the plant species that produce multiple tufts (L. stoechas, for example), you can prune each tuft with its own little dome. Most growers prune twice a year – once after all blooms are spent and once in late winter or early spring before the fresh foliage emerges. You can get away with pruning once per year if you are unable to prune twice. When pruning, it is generally recommended not to cut down into the woody part of the plant or you could risk killing it. That said, I do know one gardener who cuts theirs back almost to the ground every year and their plants seem to do quite well.

Watering

Avoid watering into the center of lavender plants from above. Doing so can cause the plant’s upright growth habit to collapse and spread in the middle, creating a hole in the foliage and this cannot be fixed. Once it happens, your plant will never be trainable back into that pretty, rounded lavender plant shape and the shrub will forever sprawl about on its elbows and knees. For best results, set your lavender plants up on a drip system or water them at their base with your hose from the side of the plant, taking care not to get water into the middle of the crown of the plant.

Frequency of watering will vary based on your climate, but generally, you want the water to drain well through the soil the day you water it so the plants aren’t sitting in water. You can water it more frequently if your soil is well-draining and your climate is dry than you could if you live in a humid area and have heavy, poorly draining soil.

Check the soil with your finger before watering. If it is dry about an inch down, it is probably safe to water.

Taking Cuttings

After your lavender plants have settled in and reached a healthy size, you can propagate non-patented varieties (there are some patented lavender varieties that cannot be propagated without paying a licensing fee) by taking cuttings in the spring and fall. It is ideal to take cuttings before the plant is flowering and when it is sending up fresh new foliage in spring. The best cuttings are around 4 inches long and are taken from shoots that have plenty of leaf nodes on the stem.

Only take cuttings from healthy, thriving plants.
Use sharp, sanitized garden snips to take cuttings. Dirty, dull snips may spread disease and harm the plant or the cutting.

Use your snips to gently cut away the leaves on the bottom of your cutting. You will probably need to cut away at least two or three tiers of leaves. An inch or two of cleared space at the bottom of the stem will suffice if there are multiple leaf nodes in that space. The more leaf nodes there are in that area, the more places are available for your stem to develop roots. Using your snips to remove the leaves will help you avoid tearing the main stem, which will help contribute to your success rate – a tip I learned from expert lavender grower Dottie Becker.

Gently place the freshly trimmed end of the stem in a flat (or pot) of moistened perlite or a lightweight mix of perlite and clean soil and press the perlite / soil down around the stem so it is nice and secure. Think of tucking a new little plant baby into bed. You want it to be snug and feel like it belongs there so it can focus on sending all its energy into sending out new little rootlets.

Perlite is a naturally occurring volcanic glass that holds moisture very well and is included in the OMRI-approved list of materials for organic growing. It will help deliver moisture to the cutting without introducing unwanted bacteria or pests to your little nursery bed. Perlite is a mined product. If you prefer not to work with it or do not have access to it, you can use another lightweight, well-draining propagation mix. Cuttings can also be placed directly into soil or a mixture of peat moss (sustainability of peat moss is questionable) and perlite.

Keep the medium moist and provide good drainage (a mesh-bottomed flat has worked best for me) and your little plant babies should be ready to plant up into individual pots within 6 to 8 weeks. If you are taking fall season cuttings, it may take a little longer for the cuttings to mature, but spring cuttings should be itching to get into the soil well within that time frame. Young plants that have not yet rooted are best kept out of direct sunlight and may benefit from a little extra humidity while they are rooting.

Hardwood cuttings can be taken in the fall. Use your snips to remove the leaves toward the bottom of the stem and then use the snips or a sharp blade to scrape away a small bit of the bark on the stem. Tuck the cutting into the perlite and proceed as before. Hardwood cuttings take longer to root than softwood cuttings, so do not be surprised if they need a little extra time in the greenhouse or a humidity tent before they are ready to plant out. You may also have a lower success rate with hardwood cuttings.

Fertilizers at this stage are optional. If you would like, you can provide a diluted 10-10-10 type (or otherwise well-balanced – look for the three numbers on the package to be fairly even) organic plant food periodically. I like to use Espoma’s organic BioTone fertilizer, as the microrrhizal ingredients seem to help the plants establish healthy root systems. Once established, lavender plants rarely need to be fertilized, if at all. I sometimes top-dress them with a bit of a balanced fertilizer in early spring.

Learning More

If you would like to learn more about how to work with aromatic plants, I hope you will join me in our Herbal Aromatherapy Certification Program™ here at Floranella! In it, I teach students how to safely and effectively work with over 100 different herbs as well as their applicable essential oils and hydrosols from the garden to the still to the apothecary. I also have a full lesson on lavenders available in our sample lessons area if you would like to learn more about lavender. You can find that lesson here. We also have a film featuring our local lavender farmers that is free to watch here. I hope to see you in class one day!