Q. How can I plant or transplant a Norfolk Island Pine? What time of year is best for planting this tree outside?
To answer the second part of your question first - the Norfolk Island pine (Araucaria heterophylla) is a tropical plant so it can only grow outdoors in the United States in the warmest part of the country (Zones 10 - 11). It you have it growing in a container then you can move it outside in any part of the country when the danger of frost has passed, or, to be safe, when the night temperature will not fall below 40º. Incidentally, the Norfolk Island pine is not a true pine but a member, along with the bunya-bunya tree (A. bidwillii) and the monkey puzzle tree (A. araucana) of the Araucariaceae family.
As to planting this tree, it prefers full sun but is not particular about soil. Note, however, that its root system is shallow so the tree should be grown in a sheltered location and may need to be staked. Norfolk Island pine can be grown in containers. It needs bright light but keep it out of full sun except for a short period each day. Cool (60-65º) conditions, falling to 50-55º at night, are preferred. For the soil, use a sandy, peaty, slightly acidic mix. The plant should be watered enough to keep the soil damp, but not soggy. In the winter let the soil dry out between waterings. Norfolk Island pine does not like its roots disturbed, so it should be repotted as infrequently as possible.
For more information on growing Norfolk Island pine as a houseplant, see our guide Popular Houseplant Profiles.
Courtesy of NYBG Plant Information Service