How to Treat a Hemlock Hedge
- 1). Situate your hemlock hedge where it is protected from drying winds. Hemlock performs best in the cooler northern climates of the United States. It is also one of the best choices for a semishady or even shady area. Site choice and soil preparation fill the primary needs of this tree.
- 2). Plant the tree at the same depth it was in its nursery pot. The soil must be well drained but hold moisture. Incorporate 4 to 8 inches of compost to the area where you will be planting the hedge. This will enhance the nutrient content of the soil and the tilth for good drainage.
- 3). Spread 2 to 3 inches of mulch around the trees. They need around the trunks approximately 1/2 inch of space that is free of mulch, for good air circulation. The mulch will gradually leach nutrients into the soil, but more importantly it conserves moisture and prevents weeds.
- 4). Run a drip hose along the bases of the hedge trees. Hemlock is not tolerant of dry soils and will need to be watered slowly and deeply to a depth of at least 12 inches. Until you get used to the soil absorption rate and needs of your trees, dig a trench alongside the hedge to physically check for dampness. The soil is kept cool and moist, but not soggy.
- 5). Prune your hemlock hedge annually in spring. Start training at planting to keep the height where you want it. You can remove as much as one-third of the plant material annually.
- 6). Use hand pruners where you can and remove wood back to a growth node. Loppers are helpful to prune out wood that is larger than 1/2 inch. Prune the top to a slight dome shape and the sides slightly longer on the bottom, so light can reach the lower foliage.
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