A novel Gram-stain-positive, rod-shaped, endospore-forming bacterium with peritrichous flagella, designated as P96T was isolated from the surface of maize roots. Strain P96T grew optimally at 28 °C, pH 7.0. The strain contained A1γ meso-Dpm-direct in the cell-wall peptidoglycan. The dominant polar lipids were diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The genome size of strain P96T was 4.8 Mb, and the G+C content was 50.01%. Phylogenomic analyses based on the whole-genome sequences classified the strain into the genus Paenibacillus. The digital DNA–DNA hybridization and average nucleotide identity relatedness analysis resulted in values below the threshold for prokaryotic species delineation, with the highest values observed for Paenibacillus enshidis KCTC 33519T (29.4 and 85.2%, respectively). Genotypic data together with phenotypic properties supported the classification of strain P96T as representative of a novel species of the genus Paenibacillus, for which the name Paenibacillus zeirhizosphaerae sp. nov. is proposed. The type strain is P96T (=LMG 32802T = NCAIM B 02678T).