Bare-root season is relatively minimal in the Santa Clara Valley because winter is so mild and dormancy of bare-root material is consequently so brief, allowing only about two months to "finish." Conversely, in Finland, similar material is likely only vascularly active for about two months during summer. We may have less time to get bare-root material into the garden, but we can fortunately dig the holes without first lighting a fire above them!

Only the deciduous fruit trees, a few deciduous shade trees, grapevines, roses, cane berries and a few assorted deciduous shrubs and vines are available bare root. Species that are evergreen are not commonly available bare root because they may become desiccated as moisture evaporates from foliar surfaces even during dormancy. Likewise, species that are very briefly dormant or are even minimally vascularly active through winter cannot survive processing as bare-root stock.

If it can be installed bare root, it should be. Such material becomes established more readily and can more easily adapt to a particular situation. For example, a "canned" apple tree has already been assigned a low branch structure that may need to be compromised if a higher branch structure is preferred. It must also recover from the stress of confinement within a can before it can begin to disperse roots. Even then, roots may experience transitional difficulty as they leave the media from within the can to extend into endemic soil. Regardless of practicality, canned material is about twice as expensive as non-canned material.

When installing bare-root material, spread out roots as much as practical to promote uniform dispersion of new roots. I prefer to form a mound of soil within the hole so dormant roots can be arranged over the mound, extending toward the bottom and perimeter of the hole. Graft unions, if present, should not be buried. The scion (above the graft) will otherwise eventually rot or root, bypassing the understock.

Flower of the Week: Moth orchid

The pronunciation of the Latin or botanical name of moth orchid suggests it might be included with a happy meal, but it is spelled like the name of an ancient Greek philosopher, Phalaenopsis. (It is pronounced something like "filet o' nopsis.") Like anthurium, which was discussed in a prior column, moth orchid is perhaps too discriminating for most garden enthusiasts but is perhaps the most commonly available orchid. Moth orchids are sometimes too appealing at the supermarket to not be brought home, but once there, can only be grown as houseplants or as greenhouse plants to be brought indoors while blooming.

Bloom naturally occurs during warm weather between spring and autumn, but blooming, greenhouse-grown specimens are available even now. A single floral rachis (stem) may be as long as 3 feet and suspends a few or many 3- to 5-inch-wide flowers. Floral color is most commonly white or purplish pink, but may be pale white or pale yellow. A smaller secondary rachis may emerge from a node of the primary rachis if the primary rachis is pruned back to a healthy node after bloom rather than removed completely. Moth-orchid plants only produce a few rigid leaves that may be nearly a foot long and a few inches wide, but these lie low and are not remarkable.

Moth orchid prefers a warm and humid environment and well-drained but moist media. Bright, ambient sunlight is best, but direct exposure to sunlight will scorch foliage. A few contemporary hybrids that produce smaller flowers may be less discriminating and more tolerant of cooler temperatures.

Horticulturist Tony Tomeo can be contacted at 408.358.2574 or at LGHORTICULTURE@aol.com.