Virginia Pine

  • Pinus virginiana

    Pinus virginiana

    Common Name:

    Virginia Pine

    General information:

    This scrubby North American native tree is most often found growing in the poorest sites and will easily adapt to most soil conditions, except alkaline soils. Capable of reaching up to 70 feet in height, Virginia Pine is more often seen from 20 to 40 feet in height with a 20 to 35-foot spread. The yellowish-green, 1.5 to 3-inch-long, flexible, evergreen needles are joined by the numerous, mature, prickly cones. The thin, orange/brown bark becomes ridged and furrowed on older trees, and is often seen due to the open branching habit.

    The Virginia pine is in some ways esthetically similar to the Japanese Black Pine, but has smaller needles and does not grow as thick a trunk. Both have purplish, flaking bark, needles in pairs, and small cones that stay on the tree.

    Family:

    Pinaceae

    Lighting:

    Full Sun. Turn the tree from time to time so that light reaches all parts of the foliage. Temperature: Zones 5 through 8.

    Watering:

    As with any pine, good drainage is essential. This pine, in its natural habitat, grows on poor dry soils.

    Feeding:

    Feed once a month from early spring to autumn using a slow- acting organic fertilizer, and applying chelated iron twice a year. If you prefer to feed using chemical fertilizers, feed the tree once every two weeks with a half-strength solution of a fertilizer meant for acid-loving plants, such as Miracid. If the foliage does not maintain a nice dark green color, you may need to treat with chelated iron to make up for an iron deficiency.

    Whichever feeding method you use, do not feed during the hottest months (July and August in the northern hemisphere), or if the tree is ailing or has been repotted recently (2-4 weeks).

    Pruning and wiring:

    Initial pruning and positioning of the roots should ideally be done at the same time as the first major pruning of the top of the tree. Subsequent pruning of the branches can be done when wiring. Wiring is best done in the fall, so that the branches will have time to become accustomed to their new position while the tree is dormant. If wiring is done in the spring or summer, the wire must be checked frequently for signs that it is cutting into the bark. If this happens, the wire must be removed and if necessary the branch should be re-wired.

    To develop the foliage, shorten the new shoots (candles) by snapping them off with the fingers just before the needles start to open up in spring, leaving 1/2 to 1 inch of shoot. Shorten the candles in two stages. First shorten the strongest candles and one week later, shorten the weakest candles. To encourage good ramification, reduce the number of end buds on each branch to two in the fall. Also in the fall, thin the needles by removing all downward growing needles and needles that are too large, removing needles from the strongest shoots first. Remove the most needles from the apex of the tree, and remove fewer needles as you work down the tree. This allows light to reach the lower branches, keeping them strong, and slows the growth of the apex.

    Every other spring, if the tree is healthy, you can remove all of the new candles. The following fall, buds will appear where the candles were removed. This serves to greatly shorten the internodes and increase foliage density.

    Spray the foliage with water daily during the summer.

    Propagation:

    Seed, layering.

    Repotting:

    Repot in spring, before the candles open, or in late summer, after the heat of summer has passed. These are the two periods of strongest root growth for pines. The Virginia pine is fast-growing, so repotting should be relatively frequent, at least every 2-3 years for young (less than 10 years) trees and every 3-5 years for older ones. Pines need deep, well drained soil, so plant in a fairly deep container. Simon and Schuster’s recommends 40% soil, 10% peat, and 50% coarse sand. Rémy Samson recommends 1 part leaf mold, 1 part loam, and 1 part coarse sand. Peter Chan recommends 1 part loam, 1 part peat, and 3 parts coarse sand.

    Pines and other conifers grow in association with a symbiotic fungus which grows in the root ball of the tree. If this fungus is not present, the tree may die. For this reason, pines and other conifers should never be bare-rooted, unless steps are taken to re-introduce the fungus to the repotted plant, such as making a slurry (thin mud) of the old soil and pouring it over the newly potted soil.

    Some experts feel that it is more important to be sure that the tree always has a healthy root system with sufficient feeder roots than to worry about symbiotic fungi. They feel that trees are more likely to die from having their root systems reduced too much at once than from not having the fungus present. Certainly it is good advice in any case to be sure the tree has sufficient roots.

    Pests and diseases:

    None of significance.

    Bibliography:

    Jahn (ed.) “The Simon and Schuster Guide to Bonsai” Murata’s “Four Seasons of Bonsai”

    Owen’s “Bonsai Identifier”

    Resnick’s “Bonsai”

    Samson’s “Creative Art of Bonsai’ Tomlinson’s “Complete Book of Bonsai” USDA Fact Sheet ST-481

    Compiled by Sabrina Caine Edited by Thomas L. Zane