If you're a busy mom who enjoys gardening but wants easy-to-grow, trouble-free shrubs and trees, yews (Taxus spp.) and hemlocks (Tsuga spp.) could be excellent choices for you. Both plants are conifers that thrive in average garden soil and can be perfect for a shady spot where many other specimens wouldn't do well. Although similar in many respects, the differences between hemlocks and yews might make one type a better choice for you than the other.
Yews in Many Sizes
Yews are slow-growing, upright evergreens that have deep green needles and produce single seeds inside a fleshy red covering. Although there are many yew species, three are widely cultivated. These are the English yew (Taxus baccata), the Japanese yew (Taxus cuspidata) and the Anglojap yew (Taxus x media), a hybrid between the other two species. All three need winter chill and don't do well in warm-winter areas. English yew grows in U.S. Department of Agriculture plant hardiness zones 6 and 7, while the other two types grow in zones 4 through 7. Yews come in many sizes and you can choose from cultivars that range in size from the 50-foot-tall "Capitata" (Taxus cuspidata "Capitata") to "Chadwickii" (Taxus x media "Chadwickii"), which is only 4 feet tall.
Hemlocks are generally pyramidal in shape, with soft, flat leaves that are shiny and green above and silvery on the reverse sides. They grow as medium- to large-sized trees, with branches that droop gently, making the tree look especially graceful. Several hemlock species are cultivated widely, including the Canadian or eastern hemlock (Tsuga Canadensis), a 30- or 40-foot-tall tree that grows in USDA zones 3 through 7, and the western hemlock, which can become 100 feet tall at maturity and grows in zones 5 through 8. The Japanese hemlock (Tsuga diversifolia) is an Asian native that's usually about 40 feet tall and grows in zones 4 through 7, while the Carolina hemlock (Tsuga caroliniana) is native to the Appalachian mountains and grows about 60 feet tall in zones 6 and 7.
The Best Light
Both yews and hemlocks are forest natives and can adapt quite well to areas in shade. Yews are relatively sun-tolerant and can grow well in a spot that gets full sun for part of each day, while most hemlocks do best in partially to fully shaded spots and don't thrive in an area subject to full sun for any portion of the day. The western hemlock is an exception to this rule, as full sun promotes bushy, dense growth on the tree, although it also grows well in shade.
Moisture and Pruning
Yews and hemlocks both need regular moisture and don't do well during dry spells, which can cause them to wilt and develop brown foliage. Adding a 3-inch-thick layer of organic mulch under the plant's canopy helps conserve soil moisture and protects it from damage. Yews are exceptionally tolerant of pruning, so you can control a yew's size or shape by pruning during late winter or early spring, just before new growth begins. Older yews also respond well to severe pruning, putting out strong new growth the next growing season. Hemlocks need little or no pruning, as it might interfere with their naturally well-balanced form, although you can prune away damaged branches at any time.