In flower, wisteria as a bonsai is a breathtaking sight. The wisteria will quickly become a rampant mess once the flowers have gone and it starts to grow.
Being a climber, in search of support, large compound leaves will spring out of long, twining shoots, growing at a phenomenal rate. These must be controlled, of course.
What happens if you don’t prune wisteria?
If you don’t prune your wisteria, it can become overgrown and unruly, potentially causing problems for the tree and surrounding structures. Here are some consequences of not pruning wisteria:
- Overcrowding: Wisteria can grow rapidly and become crowded with many shoots and branches. Overcrowding can lead to a reduction in airflow and sunlight penetration, which can cause branches to become weak and brittle.
- Damage to structures: Wisteria can grow and spread, potentially causing damage to nearby structures such as buildings, fences, and walls. Overgrown wisteria can also obstruct paths and walkways.
- Poor bloom production: Without proper pruning, wisteria can produce fewer blooms, and the blooms may be smaller and less vibrant in color.
- Pest and disease problems: Overgrown and crowded wisteria can create a favorable environment for pests and diseases, which can damage the tree and inhibit bloom production.
It is important to prune Wisteria bonsai trees regularly to keep them healthy, attractive and blooming.
Can you prune wisteria anytime?
No, it is not recommended to prune wisteria at any time of the year. It’s generally not recommended to prune wisteria during the fall or winter, as this can stimulate new growth that may be damaged by frost or cold temperatures. Additionally, pruning during the summer after the second flush of blooms has faded may not allow enough time for new growth to harden off before winter.
When should I prune my wisteria bonsai?
The best time to prune your wisteria bonsai is in late winter or early spring, before new growth appears. This is typically in February or March, depending on your location and climate. Pruning during this time allows you to shape the tree before it begins to produce new growth for the season.
Wisteria can also be pruned in the summer after the first flush of blooms has faded. This summer pruning can help encourage a second flush of blooms later in the season.
How to prune wisteria bonsai
- Determine the pruning goals: Decide on the overall shape and size you want for your wisteria bonsai. Keep in mind that wisteria is a vigorous grower and can quickly become overgrown if not pruned regularly.
- Pruning long shoots: Let the shoots grow, then prune them back to two or three leaves. After a few weeks, repeat the process when more shoots have grown. During the growing season, you may need to prune four or five times. In the following year, after flowering has ended, prune out about half the congested stubs and spurs from last year, leaving those facing upwards or outwards.
- Look for branches that are crossing or rubbing against each other, as well as any dead or diseased branches that need to be removed.
- Using sharp and clean pruning shears, make a clean cut at a 45-degree angle just above a leaf node or bud. Make sure to avoid cutting too close to the trunk, as this can damage the bark. Continue reading about bonsai tools.
- Remove suckers: Wisteria can produce suckers, which are shoots that grow from the base of the trunk. These should be removed as they can divert energy away from the main trunk and branches.
How far back can you prune wisteria?
Wisteria can be pruned back quite heavily, but the amount you can safely prune depends on the age and health of the tree. In general, you can safely prune wisteria back to within 2-3 buds of the previous year’s growth, or back to the main trunk or a lateral branch.
If you are drastically reducing the size of the wisteria or removing large branches, it’s important to do so gradually over a few years to avoid shocking the tree. This can be done by removing one-third of the branches each year over a period of three years, for example.
How do you keep wisteria small?
- Start pruning early: When the wisteria is young, start pruning it to encourage branching and prevent it from growing too tall. Prune back new growth to a few buds in the spring and again in midsummer.
- Limit the size of the canopy: As the wisteria grows, limit the size of the canopy by pruning back lateral branches to 6-8 inches in length. This will help keep the tree small and compact.
- Prune for shape: Prune the tree for shape and to encourage a bushy habit. Remove any branches that are growing too tall or too far out of the desired shape.
- Regular maintenance pruning: Perform regular maintenance pruning each year to keep the tree small and manageable. This includes removing any dead, diseased, or damaged branches, as well as pruning back new growth in the spring and midsummer.
- Root pruning: Root pruning the bonsai tree also helps in keeping the size of the bonsai tree small.
Should wisteria be deadheaded?
Deadheading, or removing spent blooms from a plant, is not necessary for wisteria. However, it can help promote more blooms and a longer blooming period. If you choose to deadhead your wisteria, wait until the flowers have completely finished blooming and the petals have fallen off. Then, use sharp, clean pruners to cut off the entire flower cluster just above the first set of leaves or buds.
Deadheading can help prevent the tree from putting energy into producing seed pods, and instead redirect that energy into producing new blooms. However, keep in mind that wisteria produces a lot of flowers, so deadheading can be a time-consuming task.
If you prefer not to deadhead your wisteria, it will still continue to bloom and look beautiful, but the blooming period may not be as long or as prolific.
Can you over prune wisteria?
Yes, it is possible to over-prune a wisteria. Over-pruning can lead to weakened or stunted growth, reduced blooming, and an unattractive shape. It’s important to avoid removing more than one-third of the tree’s growth in a single pruning session to avoid over-pruning.
When pruning wisteria, it’s also important to avoid pruning the spurs or knobs on the trunk and branches, as these are the points where the tree produces flowers. Removing these spurs can inhibit blooming and reduce the overall health of the tree.
Additionally, over-pruning during the wrong time of year can also be detrimental to the tree. Pruning in the fall or winter can stimulate new growth that may be damaged by frost or cold temperatures, while pruning too late in the spring can remove the buds that will produce flowers for the current season.
