Curly Willow Tree Care & Maintenance

The curly willow has weak branch crotches that get more prone to storm damage as the tree ages, and the thin papery bark is also easily damaged. Be on the lookout for aphids and gypsy moths, along with willow leaf beetles, which are black as larvae and a metallic blue as adults. Other insect pests that this tree attracts include lace bugs, which cause yellow leaves, and poplar and willow trunk borers. Diseases and organisms that can affect the curly willow include crown gall, willow scab, black canker and other fungi, which cause leaf spots, powdery mildew, rust and tar spots. To control insect infestations, your best bet is to check with a local arborist, but in general, the University of Minnesota Entomology Department recommends spraying larvae with a horticultural oil or insecticidal soap and adult pests with a long-lasting broad spectrum insecticide. Fungi can be controlled by pruning infected trees, raking away contaminated leaves and using a fungicide.

Considerations

Locate your curly willow in an area that can accommodate 30 feet in height and 15 feet across when it is full-grown. It's a rapidly growing tree, reaching 15 to 20 feet in three to four seasons, and its full height in just eight to 10 years. It blooms with pale yellow blossoms from April through May and should be pruned in late winter to early spring so that permanent branches will be high enough to allow the drooping branches to drape down.

The curly willow has weak branch crotches that get more prone to storm damage as the tree ages, and the thin papery bark is also easily damaged. Be on the lookout for aphids and gypsy moths, along with willow leaf beetles, which are black as larvae and a metallic blue color as adults. Other insect pests that this tree attracts include lace bugs, which cause yellow leaves, and poplar and willow trunk borers. Diseases and organisms that can affect the curly willow include crown gall, willow scab, black canker and fungi, which cause leaf spots, powdery mildew, rust and tar spots. Avoid ingesting the seeds of the curly willow, because they are poisonous.

Don't plant a curly willow near septic tanks or lines, spacing them at least 25 to 30 feet away. Their roots will enter septic lines and clog them. Avoid planting curly willows in large numbers near paved or concrete surfaces, because the shallow roots will grow upward as the tree matures and can break through the ground.

Soil

Plant your curly willow in almost any soil, including loam, clay and sand, although it prefers a soil pH of 4.5 to 8.5. Corkscrew willow trees tolerate wet soils with poor drainage. Fertilize the tree every few years after conducting a soil test to determine the nutrient levels currently present in the soil. If any one nutrient is low, you may need to use a specific type of fertilizer instead of an all-purpose product. Fertilizers high in nitrogen will promote green leafy growth, but too much can cause more leaves and fewer flowers.

Water

Curly willows prefer medium to wet conditions, with well-drained soil, although this particular species of willow tolerates drier soils better than others. A three-inch layer of mulch can help maintain soil moisture and allow the tree to grow faster.

Light

Locate your curly willow in an area that will receive full sun to partial shade, although its preference is for full sun conditions. It thrives in USDA Zones 4 to 8.

Propagation

Propagate a curly willow from cuttings by placing them in a container with moist soil and a slow-release fertilizer. Cuttings should take root directly in the pot before you transplant them.

Warning

Avoid ingesting the seeds of the curly willow, because they are poisonous.