Sunday, 29 September 2013

When to Prune Lavender

trimming a lavender bush using a Bosch hand held cutter
Cutting back lavender
How to prune lavender and when to cut back lavender are one of the most frequent questions I get asked.

Lavender has to be one of the plants on the top of my favourite plant list. Lavender has the most wonderful distinctive smell which attracts insects from far and wide, looks fabulous and is such a hardy low maintenance plant, (my kind of plant) poor well drained soil, minimal watering and it thrives... my kind of plant.

It is important to cut back lavender yearly to keep it nice and tidy, prevent the lavender from getting leggy and woody and to generate new growth. The yearly lavender prune is really the only job you need to do, and there is always the question, when is the best time to prune a lavender bush and how on earth do you do it.

When to prune a lavender bush?

There are two schools of thought here you can either prune a lavender after it has flowered in autumn before winter sets in or in the spring before summer.

I personally choose the latter as I love seeing the wintertime frost on the ends of the flower heads, simply stunning. I also believe not pruning the lavender until spring, gives the plant a little bit of protection, an insulation blanket against the cold of the winter.

There are others out there who say that cutting back lavender just after the flowers have died before the winter is best as the energy the plant uses to make seeds is saved and goes back into the plant itself.... and whilst I'm relatively new to gardening I'm always open to try new things out.

Here in the UK, the leaves are turning, falling from the trees and the temperature is noticeably cooler, autumn is setting in, and it's time to put the garden to bed and tidy up. So I seized the opportunity to prune back a row of lavender that started originally started from cuttings a couple of years ago.

This was a little bit of an experiment for me as I've never chosen to prune lavender in the autumn, but which ever time you choose, there is one important method you must adhere to when cutting back your lavender bush.

The golden rule is to cut back the stem where you see green leaf growth on the stem. Cut back any further beyond this point and you will be cutting into dead wood, and they plant will not send out any new shoots and you'll end up with dead brown patches in your bush... trust me I've learnt the hard way!!

Pruning lavender at the same height using a brick and bosh trimmer
Prune lavender at the same height to give a neat formal look
Here I'm attempting to grow a row of lavender along a brick trough, and ideally I'd like to achieve a formal look, a nice neat row of lavender at the same height.

I've seen some people use a piece of string held taught to prune a straight line, however here I used a brick as a guide (making sure first I would not be cutting into any of the dead wood at this height). Using my electric hand held Bosh trimmer it was very quick job and I was very pleased with the end result.
Row of lavender which has been neatly trimmed in autumn
Nice neat row of pruned lavender

Oh yes, not to forget, stick some of the cuttings into some soil to give away to friends, after all this  whole row of lavender was originally from cuttings.

making new plants from lavender cuttings for friends
Make new plants from the lavender cuttings
Now it's all about playing the waiting game and see how my little lavender bushes do over the winter. What will they look like come summer time next year?.... To be continued....

(PS - I've also did a prune of another lavender bush earlier this Spring... I will shortly be adding a blog post on this so please be sure to come back and visit my pruning lavender in spring blog post to see the results of the spring time lavender prune).