As always, I'll use my own garden as the lab...
Leucophyllum is one of the strongest shrubs I know. It's water efficient, quickly adapts to almost any soil and is easy to maintain. Actually, there's nothing to maintain, all you need to do is keep the following in mind:
This is a shrub that grows upward, and leaves almost no leaves behind on its main stem. Add to that the fact that it grows at a high density, and you get a wide shrub that, in season, is covered in leaves and flowers, but with "legs" that are totally naked. What that means, is that if you don't prune it on time and let it grow up, you'll soon find it has no flowers - because it can't send enough energy upwards to get the right bloom.
Tip: If you want your leucophyllum to grow new leaves along its stems and bloom again - you must ensure sunlight can enter the bush and provide air circulation. Now, lets prune!
When to prune? Early spring until early fall. Pruning leucophyllum is easy - this is such a strong plant that you could also prune it in winter. Though to keep it safe - lets not do winter.
The green fence or hedge I'm about to prune belongs to the municipality. But as they do little more than clean our sidewalk with a big noisy air blower, I don't have too many expectations for the hedge - so, I'm taking matters into my own hands. :-)
My goal for pruning leucophyllum is to renew the entrance to our home, while enjoying new growth and bloom. So, first look at the surrounding (UP MOSTLY), and if you look at the big orange arrow I drew, you will see the area above the hedge is covered in tree branches. In order to let sunlight reach the hedge I will have to cut some of these and open a path for the light to stream in. The more light, the better for my shrub, and better still for the Leucophyllum.
How to prune? Can you see the difference between the pictures? See how one has more sunlight coming from above? Can you see the thickness of the tree's canopy has changed? Great.
Now look down to the what is left of my hedge (just beneath the straight orange line). I pruned hard and it seems I had no mercy, but if you look closely, you'll notice I have left lots of small branches with leaves on them - for Photosynthesis. The next to happen, is that as sunlight and air come through the exposed stems and leaves they will encourage new growth and bloom. Which means we would have achieved our initial goal.
Where to prune? Make the cut at around half the height. Any lower would be ugly (I think) and make it hard for the shrub to recover.
I chose to prune just beneath the wall so that I have new growth and bloom above the wall - allowing me to enjoy it from inside the house.
So what will happen next? sunlight and fresh air will reach the shrub, cutting the stems hard will encourage new growth, and in 6 - 8 weeks it will all look different (I promise to upload a picture). In the mean time I'll go sweep up the leaves from the ground, pruning leucophyllum can't be all fun...what a mess....
So here we are, 6 weeks have passed since pruning leucophyllum, and although it's not blooming yet, you can see how a new growth has taken over the leucophyllum - bottom up.
But most important, take a closer look at the orange circle (top right corner) and compare it to the picture above. You'll see that I was quite brutal in cutting back the Hibiscus tiliaceus (that's it's name). I wanted to allow as much sunlight as possible to reach my bush, so that I would get the best possible results.
Bottom line - before any pruning act, I always look at the big picture.
Providing general guidelines on 'how to prune' any kind of plant is important, but there are plants, and there is YOUR plant. So despite there being loads of information on this site, I also provide specific and personalized support. If something wasn't clear, or you're not sure of your plant's name, simply send me a picture with your question. Use the form below and I'll get back to you. In the mean time, see what others are asking.