If there is one thing we get asked most about at Jersey Lavender, it has to be pruning lavender. For some reason, people seem to think that there is some mysterious wizardry to it. There really is not. It is all pretty straight forward.
The issues are when and how hard, or not, to cut back! But before I go too far, just to be clear, the following comments apply to L. angustifolia (also known as “English” lavender, “True” lavender, lavender officinalis) and L. x intermedia (also known as lavandin, lavender hybrida). Other lavenders need different treatment.
So, firstly, the when. This blog is timely, because NOW is the time (if you are in the UK) to think about, he prunes of your lavender. You need to prune when there is still some warmth in the air, when the plant is still actively growing. If you leave it too late, when it has turned cold and the plant has gone into its winter dormancy, it really will not thank you if you prune it then.
Then there is how hard? The mistake most people make is to sort of tidy up the plant by trimming off the withered, grey, dry flower spikes and the stem, cutting down to the top of the leaves. Granted, this leaves you with a satisfying-looking mound of neat foliage, BUT what you have left on the plant is that area of stem, about 3″, 10 cm long, with those leaves on. Those leaves are this year’s growth, so if that is how you prune your lavenders, then each year they will put on 3″ or 4″ of growth, that eventually turns woody, and a few years later you have a rather strange-looking, woody, leggy, lavender plant that often collapses outwards, and looks nothing like the lovely compact plant that you had before!
Finally, if you have let your lavender bush get a bit out of control, and it has become woody and straggly at the base, then it is really time to pop down to the garden centre and get a new plant. There really isn’t much that you can do to salvage them. An alternative, before you dig it out, is to take some cuttings to produce your own new lavender plants for your garden.
So the right way to prune is to be a little more brutal and cut off much of that leaf bulk. Cutting down to around the lowest set of leaves is about right. Typically, just below these leaves you see tiny, greyish buds. When the plant HAS leaves, it doesn’t need to do anything with these buds. They are sort of “in reserve”. BUT when you prune off much of the leaf bulk, these buds will really get going and push out new shoots. Also, wherever a leaf joins the stem, in the cleft between the two, you have a shoot node which will push out. You may also find rather straggly shoots from lower down, that cannot get enough light whilst all the flowers and leaves are on the plant. Prune off much of the leaf bulk and these shoots can finally get some light and strengthen up.
When pruned properly, you might stand back and go, “Uh-oh, what have I done!” Believe me, your lavender plant will love it and bounce back with fresh foliage that will have a chance to slow down and prepare for winter as it gets colder. In fact, I believe that and annual pruning is THE most important maintenance job to carry out on your lavenders is you want them to be strong, healthy, compact plants year after year.
Should I Prune My Lavender In Spring?
Even though it is still stubbornly raining and the fire on our lovely Jersey Lavender Farm is still being regularly lit, clumps of snowdrops are beginning to speckle the verges, and we’ve even seen a few daffodils. So yes, even though it might not quite feel like it yet, spring is on its way. And along with the arrival of spring, there also comes those first annual gardening jobs. Spring is the time to tidy and weed your borders, give your sad lawn a feed and tie trees, such as conifers, that have been spread by snow. But is spring the time to prune your lavender?
This is a question that we regularly get asked, as many gardening books and online resources will give you differing answers; some say prune in spring, some say prune in autumn and some say dead-head throughout the year. So what should you do? The answer actually depends on the type of lavender that you have.
Lavender Angustifolia and Lavender Intermedia
These hardy varieties should be pruned just after flowering, in late summer or early autumn. This is the time when we harvest our lovely Lavendula Angustifolia plants, ready to dry the lavender buds or distil our amazing velvety lavender essential oil.
You can cut back these varieties of lavender quite hard, taking out at least two-thirds of the new growth, just making sure that you leave some small shoots of that year’s growth below where you cut. If you cut it back too hard, you will find that lavender is unable to sprout from old wood, and you will have to remove and discard the plant. If pruned correctly, though, you will find that by mid to late autumn you will have a neat mound of new foliage on the plant ready to flower next year. Or if you are really lucky you might even get a second autumn flowering.
Lavender Stoecha
These varieties of lavender should be pruned in early summer after their first flowering, and then simply dead-headed throughout the rest of the summer. If treated correctly, these varieties of lavender will give you at least two flowering each year. However, it is important not to prune these types of lavender after September, or you will cut off next year’s bud forming shoots.
Lavender Dentata, Pterostoechas and Allardii
These more tender types of lavender need more gentle handling and are not quite as hardy as their cousin’s Angustifolia and intermedia, but if kept happy will flower almost continuously throughout the year. In this case, you need simply to keep on top of dead-heading them as you go along and prune only gently to keep the plant in shape, during their active growing season.
