When and how to prune a bougainvillea?

Why prune the bougainvillea?

Bougainvilleas are climbing bush plants, meaning they form long woody stems, allowing the plant to spread by climbing. Above all, the pruning of bougainvillea serves to:

• shape and guide the plant as you wish,
• balance the branches,
• limit its growth in width and height,
• encourage its flowering.

In essence, pruning bougainvilleas is not really essential for the plant; even unpruned, it will have an abundant flowering.

Good to know: As bougainvillea is woody, its young flexible stems will harden and form wood. At the base, one or more trunks will form, and the main stems will take on an increasingly larger diameter, forming true branches.

In addition to pruning bougainvillea, you will need to train the plant on a support or stake it, to give it the desired shape and guide the shoots until they become hard. They can be tied to the support, but the hooked thorns help the plant cling, with the branches intertwining.

The little note from Sophie: Bougainvillea does not produce tendrils or climbing roots to cling to the support by itself, as other climbers might. Be careful, this beautiful bush is thorny: to avoid injuries, wear sturdy gloves when pruning and training it!

Pruning bougainvillea and training it aim to guide the plant to the desired shape

When to prune a bougainvillea?

Two important things to remember when pruning your bougainvillea:

• Wait until the risk of frost has passed: pruning of the bougainvillea should be done at the end of winter or preferably at the beginning of spring.
• The bougainvillea flowers on wood that is 2 years old. Therefore, it is necessary to prune the shoots of the year to avoid compromising flowering. In this case, you can also prune the bougainvillea just after its flowering, at the end of summer.

How to prune a bougainvillea?

Tools for Pruning Bougainvillea

Before you start pruning bougainvillea, make sure you have the right tools:

• a well-sharpened pruning shear,
• a branch cutter to remove old, thick, and hard branches,

Tip: To prevent the transmission of diseases between plants, be sure to clean your cutting tools thoroughly before and after pruning bougainvillea.

How to Prune Bougainvillea in the Ground?

Pruning bougainvillea in the ground is generally done at the end of winter or very early spring, depending on your climate.

1. Start by removing any shoots that disrupt the plant’s shape.
2. Then, cut back the new shoots inward to thicken the foliage.
3. Long, flexible stems (known as voluble) can be cut back to 3 or 4 nodes (the junction of leaves on the stem) to control their growth.
4. Also, remember to remove dead wood and, if your bougainvillea is very bushy, thin out the interior a bit to allow better light circulation.

How to Prune Bougainvillea in a Pot?

Pruning bougainvillea in a pot helps maintain a balanced and easily movable plant. It is best done after flowering, at the end of summer.

1. Remove any overly long or unruly branches, and reshape the plant to your preference: bushy or on a stem.
2. Don’t hesitate to remove dead wood and shorten overly vigorous stems.

In a pot, bougainvillea tends to grow quickly, so it’s best to prune it annually to keep it compact and easy to winter.

How to Prune an Old Bougainvillea?

Pruning an old bougainvillea helps restore vigour to a plant that may have spread too much or is flowering less. Intervene at the end of winter or just after flowering.

1. Start by removing dead wood and any very old branches.
2. You can also remove one or two large branches each year to gradually renew the foliage.
3. Shorten the long stems and centre the plant to give it a nice shape. This will help your bougainvillea produce new shoots and flower generously again.

How to Prune Bougainvillea to Train it as a Bush?

Bougainvillea is considered a climbing plant, as its branches can extend over metres and thus climb vertical surfaces. However, there’s nothing stopping you from pruning bougainvillea as a shorter bush to diversify its use or give it a bushy shape on a more or less high stem.

Again, keep in mind that for cultivation in the ground, you need to ensure that your region is suitable or at least plant the Bougainvillea ‘Violet de Mèze’, hardy down to about -8 °C.

To prune bougainvillea as a bush:

1. Select a main stem to grow vertically, removing lateral shoots at the base.
2. Once the desired height is reached, pinch (cut) the tips of the stems to encourage branching.
3. Prune regularly to maintain a rounded and balanced shape. This method is particularly well-suited for potted bougainvilleas, especially for small terraces or balconies and even in borders.

Pruned Bougainvilleas as Bushes

After pruning bougainvillea: training and staking

The support must be installed at planting. It depends on the location of your bougainvillea and how you want to train it:

• a vertical support such as trellis or metal wires to train it vertically against a wall
• a rounded arch to guide it over a gate, entrance, or path
• a pergola, a gazebo, or a carport to shade and flower a terrace or parking area
• a fence to dress up a boundary instead of a hedge
• a stake to keep it in a pot or to give it a standard form
• a large container with a trellis to grow it in a way that allows you to protect it from the cold

In addition to being decorative, the support must be sturdy and well-secured. Remember that your bougainvillea is a vigorous plant that can have significant growth, and its weight must be partially supported by the support. Bougainvillea plants are often sold tied to a small bamboo stake, which is only sufficient for nursery production but will not be adequate later on.

At planting, spread the main branches and tie them to the support to guide them into the desired shape.

Always prefer specific ties for climbing plants that will not damage the plant’s stems and that you can loosen. You will then need to guide the flexible branches onto the support as they grow. Once the branches have lignified (formed wood), you can remove the now unnecessary ties.

Arch, pergola, or trellis: the type of support depends on the chosen location for your bougainvillea