In Ireland , Pinus pinea is by far the most likely to produce regular crops of nuts. In coastal locations. Pinus torreyana has good potential while on more sheltered sites Pinus sabiniana, Pinus Coulteri and Pinus gerardiana are worth trying. The subalpine pines Pinus albicaulis, Pinus koraiensis and Pinus cembra also have good potential, but are very slow to come into production. Pinus pumila, the dwarf Siberian pine produces small nuts suitable for production of nut oil. In spite of its name, Pinus pumila grows quite quickly in Ireland, much faster than the subalpine pines listed above. All pinenut species are strongly outbreeding so single trees may not produce nuts. For best results plant 3-4 trees of the same species.
Pinus cembra , the Arolla stone pine, is native to the Alps and Carpathians, where it grows at a higher altitude than any other conifer. It is a very tough tree, capable of thriving in barren stony soil. In its harsh native environment it can take decades to reach nut-bearing age but when cultivated the first nuts appear at about 15 years. Requires well-drained soil. Slow growing, eventually reaching ten to twenty metres. Hardiness Zone 5. For best results, plant more than one tree.
Pinus koraiensis , the Korean stone pine, is native to Korea, Northern China, the Pacific coast of Russia, and Northern Japan. Closely related to Pinus siberica, but thought to be more adaptable to Irish conditions. It should produce the first nuts after about 15 years. Can tolerate a wide range of soils. Will grow into a large tree. Also valuable for timber. For best results, plant more than one tree. Hardiness Zone 3.
Pinus pinea, the Medierranean stone pine, grows well in Ireland and will produce the first nuts after 8-10 years. It is a tough hardy tree, tolerant of frost to -15°C. It will grow in any well-drained soil. Very good in coastal locations. This is by far the best choice of pinenut tree for Ireland. Slow growing with spreading habit. Also valuable for fuel. For best results for nuts, plant a minimum of 3-4 trees. Hardiness Zone 8
Pinus pumila, the dwarf Siberian pine, is native to the Russian Pacific coast, Northern Japan and parts of Korea and China. Closely related to Pinus koraiensis and Pinus siberica. It forms a dwarf tree or large shrub, occasionally reaching six metres. Compared to other pinenuts, the nuts are very small. In Siberia and parts of Japan the nuts are harvested for their oil. Of the pinenut trees offered here, the most suitable for really tough situations. Very suited to mass-planting in harsh coastal or upland environments. Compared to its subalpine relatives, grows relatively quickly in Ireland and could be used for as a nurse tree for other low growing species. Hardiness Zone 5.
Pinus siberica, the Siberian stone pine, is closely related to Pinus cembra, the Swiss Stone Pine, but produces larger nuts. It is a long-lived tree (c500 years) that in its native environment can grow to 30 metres. Although it has evolved to cope with the extreme temperature variations of Siberia and Mongolia, it appears quite comfortable in cool temperate climates. Known to be growing in coastal regions of some Baltic countries. Nut-producing capability in Ireland is unproven, but appears possible. Probably best on a cold upland site. The first cones should appear after about 15 years. Also valuable for timber and fuel. For best results plant more than one tree. Hardiness Zone 3