Soil Requirements for a Tricolor Beech Tree
Delicate beauty appears in the pale pink, cream and green variegated leaves of the tricolor beech (Fagus sylvatica 'Purpurea Tricolor'). A selection of European beech, grow it in USDA Zones 5 through 7 where winters are cold but summers warm and not overly intense. Avoid disturbing tree roots, such as through compaction.
Even though varieties of European beech including 'Purpurea Tricolor' generally tolerate different soils better than the American beech, the finest growth occurs when soils are fertile and deep. Loam soils derived from compost yield best growth, but any sand or clay soil that has organic matter suffices, especially if the soil depth extends beyond two feet and is not atop a hard rock sublayer.
Grow the tricolor beech in a non-alkaline soil, ideally acidic, with pH reading below 7.0. Neutral or barely alkaline soils (those at or above pH 7.0) become better suited to the beech tree if acid-forming compost or mulch is scattered over the tree root zone. Pine bark, oak leaves, peat, or pine straw/needles decompose and gently lower soil pH.
Never plant a beech tree in a soggy soil or in a location that potentially floods after a heavy rainfall. The tricolor beech needs a consistently moist, but well-draining soil. The use of an organic mulch layer, 3 to 4 inches deep over the root zone of the beech tree, helps retain soil moisture and moderate soil temperatures, especially in the heat of summer or when the natural rainfall regime is low. Mulch is particularly important for fast-draining and temperature-changing sandy soils, although all soil types improve with the mulch layer.
Beech roots tend to grow in the top inches of soil, especially if in a fertile, moist soil with organic mulch layer. Heavy, dense soils that compact from foot or vehicular traffic make poor choices or locations to plant the tricolor beech. Note that all soils compact more tightly from weight if compressed when moist.