Neocolonialism
During the age of imperialism, European powers conquered African lands and ruled them as colonies. As African nations began to throw off their colonial rule and become independent in the mid-20th century, they began to form their own governments and seek to establish control over their economies. However, most of them became almost immediately privy to neocolonialism, which is where foreign investors and local ruling elites partner to "invest" in the country, but instead return said country to an almost colonial type of relationship. They are now subject to market forces, loans, transportation changes, and local corruption. Ngugi chronicles Ilmorog's experience with neocolonialism, showing that all of the new modern developments merely hid the fact that the people were losing any power of their own.
Love and Passion
Love and passion are not always one and the same in this novel, nor are they always sustaining, fulfilling, or healthy. Munira, for example, is obsessed with Wanja, but this passionate obsession destroys him. Kimeria's obsession with her leads to a myriad of problems. Karega actually loves her, but the two of them cannot sustain their love due to his need to develop his workingman's consciousness. Only Abdulla has both love and passion for Wanja, which is reciprocated; it is telling that he is the father of her unborn child.
The Value of Human Life
When the villagers arrive in the towns that surround their nation's capital, they are turned away by a priest who could have helped them. The holy man doesn't even react when they say they have a sick child with them who might be in serious peril. Then when they get to town, there is a domineering man (Kimeria) who harasses them and rapes Wanja. These are meaningful examples of the disregard of human life that people in power display. Additionally, they are only there to request better treatment from a government that currently offers them no support, and it only offers that support when it is advantageous to do so.
Community and Brotherhood
The novel suggests that while the individual has value, it is the community that truly matters. Ilmorog is comprised of numerous individuals and only their collective work can make the village survive, only their collective endeavor can make the journey to Nairobi possible. Their understanding of their past and how they are part of a wider African and Third World community also matters; strikes and protests only work when there are many bodies, rituals are more meaningful when a wide array of people take place. Ngugi suggests that the people must come together to wrest their land and their culture and their future back from predatory outsiders.
Christianity
Christianity preceded the colonizers in Africa and then established itself as a powerful way in which the colonizers justified their actions and maintained power over the local population. In Petals, Christianity is depicted as a religion dominated by fanatics and colonial and neocolonial collaborators; it is foreign and out of touch. Those who embrace it, such as Rev. Jerrod and Ezekieli, have no sympathy for the people and can offer no real aid. They are full of "prayer" and advice, but not the food, medicine, or sympathy people really need. Munira's embrace of evangelical Christianity further exacerbates his proclivity toward obsession, selfishness, and cravenness.
Education
Ngugi demonstrates a complicated view of education in the text. He is certainly in favor of it, evinced through Wanja's lamenting that she did not finish school and had to be a barmaid, as well as her fervent support of Joseph, who is the next generation of Kenyan youth and someone who might be able to carry on the struggle. But Ngugi also finds education problematic, especially when it is shaped by foreigners and/or foreigners' collaborators. In that case, it cannot meet the people's needs for it does not tell them of their own history, their own culture, and how to understand themselves. It cannot explain the problems that plague them and it offers no solutions. Only a truly African education system is of value.
Local and Global Struggle
Though the novel is about one village and is thus a small, intimate narrative, it is also much more than that. It is also the story of Kenya, the story of Africa, and the story of all places colonized and controlled by Western powers. Ilmorog could be anywhere in Kenya or Africa, in Latin America; it could be India or Vietnam. Ngugi sees it as vital that local people see themselves as part of a larger struggle.
