Growing Cornus (Dogwood)
Latin Name Pronunciation: kor'nuss
CULTURE: The Pagoda Dogwood (C. alternifolia) and Dogwoods with variegated leaves fare best in partial shade. Site Cornus canadensis in partial to full shade. For other Dogwoods, choose a site in full sun to part shade. Varieties grown for the color of their stems or autumn leaves will give their best performance in full sun. Grow Dogwoods in moderately rich, well-drained soil; they can take a soil that is evenly moist but not soggy. Cornus canadensis prefers cool growing conditions and moist, slightly acidic soil. Dogwoods seldom need fertilizing and have few insect or disease problems.
Space shrubs such as C. alternifolia, C. sanguinea, and C. sericea 3–5′ apart; they will become 5–9′ tall at maturity, depending on variety and pruning. Trees such as C. controversa, C. elliptica (aka C. angustata), C. florida, and C. kousa will grow from 10–30′ tall at maturity and should be spaced accordingly.
BAREROOT TREES AND SHRUBS
On arrival: Your bareroot tree or shrub has been stored in a temperature-controlled cooler, which simulates winter and keeps the plant dormant. Dormant plants are unaffected by cold weather and can be planted as soon as you are able to dig a hole in the ground. If you cannot plant immediately, your tree or shrub may be stored upright in its wrapping material in a cool, dark place such as a basement, garage, or unheated shed, for a week or so. Keep it away from direct sun.
PLANTING A BAREROOT TREE OR SHRUB: Select a spot in your garden that is sheltered from strong winds. When you’re ready to plant, unwrap your plant and remove the packing material.
- Soak the roots of your tree or shrub in a container of water for a couple hours to rehydrate them.
- Dig a hole wider than the spread of the roots and deep enough to accommodate them, allowing for adjustments.
- Use excavated soil to form a mound in the center of the hole.
- Set the plant on top of the mound, fanning its roots outward. Adjust the height of the mound by adding or removing soil until the plant is positioned so that the crown (where the roots meet the stem) is at the surrounding soil level. Roots should all be below grade when the hole is filled.
- Check from all sides to make sure that the trunk is perfectly upright, not leaning in any direction.
- Backfill the hole with soil about halfway and water well, allowing water to soak in and settle the soil. Re-check for upright trunk alignment. Then add remaining soil to the top of the hole, creating a little dam around the outer edge, and water again.
- It is best to stake a young tree for extra support until its trunk attains sturdy proportions. Choose a stake that has a diameter at least as large as the stem’s diameter and long enough that when pushed firmly into the soil, it reaches inside the branches of the tree. Fasten the trunk to the stake at several points with garden twine or soft ties, allowing for some movement. Check the ties periodically and loosen them if they constrict the outward growth of the stem or dig into the bark.
ESTABLISHING A BAREROOT TREE OR SHRUB:
- Do not fertilize when planting or for the first growing season.
- Because a bareroot plant is dormant, it cannot take up much water. Refrain from watering after the initial planting until your tree or shrub leafs out and begins actively growing, unless you are experiencing extreme drought conditions.
- Minimal pruning is needed until one or two growing seasons have passed, although any suckers or growth that sprouts from the trunk or rootstock should be promptly removed.
- Once the plant has broken dormancy and is actively growing, care for it as described (except for fertilizer recommendations, although compost and mulch are recommended).
PRUNING: Stems of C. alba, C. sanguinea, and C. sericea provide the best color in full sun (and will resprout vigorously) when cut to within 12″ of the ground every 2 to 3 years. Prune in late January to very early March in Zones 4–7, earlier further south, before the sap begins to rise. Pruning of other shrubs and trees consists of removing any dead or weak growth and shaping as needed, in early spring.
GROWTH: Growth rates for C. florida and C. alternifolia varieties are slow when first planted, then moderate once established. C. kousa is slower growing. Other Dogwoods may grow 25″ or more a year if conditions are good.
SUGGESTED USE: Plant shrubs and trees behind perennials, in a shrub border, along a roadside or by a pond. C. canadensis is lovely as a ground cover or in a wild flower garden.
