P. zombamontana is a shrub or small tree with hairless leaves that are opposite each other, oblanceolate, obovate to elliptic, and can grow up to 15 cm (5.9 in) long.

The leaves have relatively parallel lateral veins that are slightly sunken above, and without any domatia.

Its flowers grow in branching auxiliary inflorescences and are small, white to pale-creamy-yellow in color.

The round fruit is around 6 mm long and slightly ribbed with a yellow to orange-red hue when ripe.

It is one of the primary pioneer species of secondary montane forests and may be abundantly plentiful in the understorey.