Willow Hybrid – Growing and Care Guide
Willow hybrid trees are one of the fastest-growing trees in the world. They typically gain between six and ten feet in height each year, though, in ideal conditions, this can increase to as much as 20 feet each year. They have many excellent qualities that make them easy to grow in a wide range of situations. They have a very strong root system, which means they can be utilized as erosion control. They also have a dense growth habit that makes them useful as privacy screening, as well as windbreak screening because they are very tolerant of strong winds.
Willow hybrids have excellent resistance to pests and are very rarely bothered by any type of infestation. These plants will adapt well to a wide range of soil types and can even thrive in clay or poor soil. They have the ability to contribute to the decontamination of water and soil in wetland areas, and despite the fact that they have fast and vigorous growth habits, these trees are not invasive.
Added to this, willow hybrids are very attractive and ornamental. They feature the types of lance-shaped leaves you would associate with other willows. As a deciduous plant, the foliage arrives in spring, with slender leaves that are light green on the upper surface and a paler green beneath. The foliage will develop to a yellow shade in autumn before dropping to the ground, though the skeleton of the tree is attractive and so retains interest through winter as a bare tree.
Willow hybrids also produce attractive catkins, which can be made up from tiny yellow or green flowers, and will either be drooping or upright. As most willow hybrids are sterile, they do not develop the cotton-like clusters of seeds that can be seen on native willows.
Willow Hybrid Overview
|Scientific Name||Salix x matsudana x alba|
|USDA Hardiness Zones||4-9|
|Type||Deciduous tree or shrub|
|Common Names||Willow hybrid, Austree willow|
|Height||Up to 75 feet tall|
|Light||Full sun to partial shade|
|Watering||Maintain average to moist soil|
|Pests||Highly resistant to pests|
There are several varieties of willow hybrids. They can be naturally occurring hybrids or man-made hybrids formed in cultivation. The popular Weeping Willow is a hybrid, which occurred by crossing the white willow (Salix alba) with the Peking willow (Salix babylonica). Other varieties of willow that are produced via hybrids include:
Japanese Dappled Willow-Salix integra ‘Hakuro-nishiki’
This willow is notable for its variegated foliage. The leaves emerge in the spring in a pretty pink color, and as they mature, they can take on hues of green or cream. In the fall, the leaves become yellow before dropping to the ground. This compact shrub or small tree will often have several different colors of foliage on it at once, as they all progress into various colors at slightly different stages. The branches of the plant are orange-red, which gives further interest to the landscape when the tree is bare through winter.
Golden Curls Willow-Salix x sepulcralis ‘Erythroflexuosa’
This tree is a result of crossing the Golden Weeping Willow (Salix alba ‘Tristis’) with the Corkscrew Willow (Salix matsudana ‘Tortuosa’). It can be grown as a large shrub or small tree and produces tendril-like branches that twist and curve in a gentle downward direction. It has received the Award of Garden Merit from the Royal Horticultural Society for its ornamental quality and ease of growth. It suits sunny sites best, with soil that is consistently moist.
Caring for Your Willow Hybrid
Willow hybrids are highly adaptable to a range of different soil types, which is great news because it means you should be able to grow one of these plants easily, regardless of what type of soil you have in your yard. Even soils that are typically considered as undesirable for most plants will be suitable for growing a willow hybrid in, including clay or rocky soils.
For best growth, willow hybrids prefer a neutral soil that is well-draining. They also do well in soils that are slightly acidic or slightly alkaline, but even soils that do not meet these requirements should fare just fine. The most important factor in growing a willow hybrid is ensuring that the soil it is growing in is kept moist, at least when the plant is young. Therefore, the only soil that is an absolute no-no for willow hybrids is dry soil.
If you have purchased your willow hybrid from a nursery and it is in a container, or if you have grown it from a cutting in a container, then you can plant it in the ground at any time of year. If you have a bare root willow hybrid, which is typically what you will receive if you buy this plant online, then you should plant it outside between November and May. This is because bare-root plants are more susceptible to drying out, which is more likely to happen during hot and dry months; therefore, the risks are minimized if you plant it outside during cooler and wetter months.
To prepare a space for your plant, dig a hole in the ground that is between two and three times the size of the existing root ball. Set the root ball into the hole and fill it halfway back up with soil, then add a generous amount of water. As the water drains, it will help to settle the soil and get rid of any air pockets, which can cause the roots to dry out. Once drained, fill the remainder of the hole with soil, and deeply water it again.
The soil should reach the same level on the plant as it did in the container. Because willow hybrids rely on consistently moist soil when they are young, it is a good idea to create a water well around the base of the plant. To do this, create a circular wall around the trunk of the plant, measuring between two and four feet wide, with soil. The soil ‘walls’ are basically mounds, which should be around five inches tall and two inches wide. Fill this well with water each time you irrigate the plant, ensuring it has plenty of access to the required moisture.
Depending on the type of willow hybrid you have, these trees can grow as large as 30 feet wide, so ensure you plant your tree in an area with sufficient growing space. If you want to create a privacy screen with willow hybrids, they can be planted between five and ten feet apart.
Willow hybrids, when young, rely on generous amounts of water to thrive. For the first few months after you have planted your willow hybrid, you should water it liberally twice a week or even more frequently in hot climates. After this period has passed, you should continue to water the tree at least once a week until it has been growing in your garden for a full year. During times of drought, increase your watering to account for the lack of rainfall.
These trees tend to fare especially well when grown alongside streams or on riverbanks, where the soil remains naturally moist constantly. Willow hybrids typically shed their leaves as a sign that they are not getting the water they require, so watch out for this and increase your watering schedule if it happens to your tree.
If you want your willow hybrid to continue to grow rapidly, then you should continue to keep its soil consistently moist. If you are less interested in rapid growth, then you can gradually cut back on watering, and the tree will adapt to surviving on less moisture, providing it is mature enough to handle this. Mature willow hybrids can survive in dry soil but can struggle to gain height as a result of this.
To help your willow hybrid retain the moisture, it’s a good idea to mulch around the base. Create a two-inch-thick layer of mulch over the top of the soil, leaving a few inches around the trunk so that the mulch doesn’t come into contact with the plant and cause rot. Mulching over the soil will prevent moisture evaporation and allow the soil to retain more moisture for a happier willow hybrid.
Willow hybrids will thrive in either full sun or partial shade. They are fairly heat-tolerant and so will perform well in full sun, which is where a plant receives a minimum of six hours of direct sun each day.
If you live towards the higher end of the recommended USDA hardiness zone for this plant, then you might want to consider positioning it in partial shade, ideally with shade provided in the afternoon when the sun is at its most intense. This will prevent the tree from being damaged in very high temperatures. Even in cooler regions, the willow hybrid will thrive in partial shade. Partial shade is considered to be around four hours of direct sun each day, with the remaining time spent in the shade.
Willow hybrid trees are recommended for growing in USDA hardiness zones 4 through to 9, which covers a wide range of temperatures. These trees are fairly tolerant of heat and can also withstand temperatures as low as -20º F. As well as being cold hardy, they are also very tolerant of cold winds, and therefore are ideal for use as windbreaks. Their dense growth habit can be utilized as a barrier; for example, you could plant these trees along your driveway to prevent drifts of snow from settling, and therefore saving you time shoveling snow in the winter.
Willow hybrids can be propagated with good success from cuttings. Cuttings can be taken at any time of year, though propagation is typically most successful during spring and summer. Use softwood or hardwood, and take a cutting of around six to eight inches long. These can then be planted, cut end down, into pots filled with soil and compost. Ensure that several nodes are buried beneath the soil’s surface and that the soil is kept moist but not wet.
While you may want to use a rooting hormone to increase the likelihood of success, this is not necessary with willow hybrids. Willow plants contain high levels of natural rooting hormones, and in fact, willows are often used in the process of making homemade rooting hormone. Therefore, using additional rooting hormone is unnecessary, as these plants will root well by themselves.
Roots will begin to develop as quickly as two weeks, but in some cases, they can take many months. This will be dependent on various factors, such as the type of cutting you used and the time of year. Willow hybrid cuttings typically have a high success rate for propagation, so if your cutting doesn’t seem to be forming roots, just have patience and wait for it to do its thing; it will likely get there eventually.
These trees do not need to be pruned and will naturally create their own attractive shape. They are considered to be self-pruning, and the wind will remove any weak or damaged branches. However, if you wish to prune your willow hybrid, it will respond well. These trees should be pruned in early spring, with cuttings made at a 45-degree angle.
Pruning the tree will encourage growth and result in it becoming more densely branched. You might also want to prune it to keep the size under control if it is getting too big for the space. Willow hybrids will tolerate heavy pruning, and you can remove as much as two-thirds of the branches without any issues. If you are growing your willow hybrids into a hedge, then you can expect to need to prune these twice a year to maintain a uniform, neat shape.
Willow hybrids should be fertilized annually. Use a slow-release balanced fertilizer each spring as soon as new growth begins to emerge.