The most striking feature of secondary walls is their loss of plasticity. Progressive depositions of new lamellas thicken the wall while the cell lumen's diameter decreases. Mostly are secondary walls less hydrated than primary walls and contain less pectins and hemicellulose. Instead are other components deposited , which are sometimes characteristic for certain cell groups or tissues. The lignins of the single plant groups differ in the percentages of these starting compounds and in the way they are linked.
All bonds leading to the formation of a three-dimensional molecular network are covalent.
Only vessel plants contain lignins. The lignin of pteridophytes consists mainly of coniferyl alcohol polymers, in dicots occur coniferyl and sinapyl alcohol in roughly equal amounts. In the lignins of all plant groups are only trace amounts of coumaryl alcohol found. Mannanes are a structural element of many seeds, the walls of pollen contain sporopollenin, a polymerization product of carotene. Many secondary walls contain a wide range of strongly hydrophobic compounds, like suberine , the basic component of cork.