Quercus palustris 'Pingreen' GREEN PILLAR^®

It is always so nice to learn about a new plant that represents a smaller version of a large species just because many of us want to enjoy its features without having to fear that it will take up the whole of our garden. GREEN PILLAR^® is one of them. It is a narrowly columnar variety of pin oak which keeps itself very slim – about 1m wide in about 10 years. Why would you go for this oak rather than the fastigiated form of English oak? The main difference are the typical pin oak leaves. They are deciduous, deeply lobed, and glossy. They emerge fresh green and retain its rich green colour until autumn when they change to fiery orange and red if cultivated in acid soil. The display of vibrant red shades on a slim tree makes a fantastic landscape feature.

GREEN PILLAR^® was found and introduced by William Flemmer III from Princeton in New Jersey, USA, in 1994 as a consequent mutation of another variety called Crownright. It is patent protected, registered under No. PP9,093.

Pin oak will grow in almost any soil type, including chalky, but it will have the most spectacular autumn colours only in acid soil. Being also called swamp oak it will grow in moist and wet areas, too, but only if given enough time to establish in conditions that will not allow the transplanted root-ball remain water-logged before new roots are made. Hardy to about -34°C (USDA zone 4).

Last update: 11-02-2013