Psychotria viridis is native to the Amazonian lowlands, but is also cultivated throughout northern South America and much of Central America. It is an evergreen tropical tree or large shrub growing in full sun to half shade. It has large (up to 24cm) leaves, which are oval with pointed tips. Its small brown seeds are shed from red berries. It usually grows in very rich and fertile soils.
Chacruna will do best in a part shade position, as well as being generally taller and a healthier greener colour. Plants placed in a full sun position will have more yellowish/lighter green coloured leaves as well as having smaller leaves. I think the ideal shade percentage is 30-50% if you are growing under cover. They are tolerant and deep shade can be preferable to a full sun position in Australia
Prepare a free draining growing medium. Something like equal parts vermiculite, sand and potting compost would be about right.