Fast growing and hardy, willow grows easily into a green hedge, a wind break and a visual barrier. Multi-stemmed varieties of willow grow into dense thickets. With pruning and care these voracious growers can be shaped into a quick green hedge. The Latin name Salix includes the large willow trees as well as brushy shrubs that are used for growing willow hedges. Willows grow fast from cuttings, can survive in poor, wet or boggy soil, and prosper in the UK's temperate climate.
Collect willow cuttings from a willow shrub during the late autumn or early spring when the ground is unfrozen but the plant is in its dormancy period; between November and February is ideal. Make the cuttings anywhere from 60 to 180 cm (2 to 6 feet) long. A single branch can be made into multiple cuttings.
Make the bottom cut at a 45-degree angle and the top cut at a horizontal angle to later help determine which end goes in the soil. Plant the cuttings right-way-up in order for roots to form successfully.
Remove all the leaves from each cutting by pinching them off or by clipping them close to the stem. Avoid pulling them off so as not to damage the cutting.
Place the cuttings, bottom-side-down, in a bucket of water to keep them moist until planting time. Willow cuttings can be stored for three to five days in water before planting but can also be planted immediately.
Determine the line that the willow hedge will follow. To keep the line from wandering during planting, stretch a string between two stakes along the desired length of the hedge.
Plant the cuttings about 30 cm (12 inches) apart. In soft ground, simply press the cuttings into the ground with the angled cut going into the soil. In hard ground, either soften it with water or make a hole first using a metal bar about the width of the cuttings. The bottom third of the cutting should be below the soil line.
Keep the soil around the cuttings damp for the first growing season. In wet winter and spring weather, little or no watering is necessary. In dry weather, apply enough water to each cutting so that the soil remains damp to the depth of the cutting. Apply water when the top 25 cm (1 inch) of the soil begins to feel dry to the touch.
Prune the hedge in the late winter to encourage a compact tidy shape. Willows are fast growing and can withstand heavy pruning. Willows cut back to the ground will regrow vigorously within a season or two. Willows will also thrive with little or no pruning, taking on a brushy wild look.
For a living hedge, golden willow (Salix alba var vitellina) and coral bark willow (Salix alba subsp vitellina Britzensis) are well suited. These varieties have yellow or red stems that are visible in the winter when the leaves are gone. These varieties are both multi-stem willow varieties that will grow into a dense thicket.
Other good varieties for a living willow hedge are pussy willow (Salix caprea), violet willow (Salix daphnoides), rosegold pussy willow (Salix gracilistyla Melanostachys) and dappled willow (Salix integra Hakuro-nishiki).
Willow roots can be invasive. Avoid planting willows near sewer lines, septic systems and other underground structures.