Production of even-parity charmed mesons in hadronic $B$ decays is studied. Specifically, we focus on the Cabibbo-allowed decays $\overline{B}\ensuremath{\rightarrow}{D}^{**}\ensuremath{\pi}$ and ${\overline{D}}_{s}^{**}{D}^{(*)}$, where ${D}^{**}$ denotes generically a $P$-wave charmed meson. While the measured color-allowed decays ${\overline{B}}^{0}\ensuremath{\rightarrow}{D}^{**+}{\ensuremath{\pi}}^{\ensuremath{-}}$ are consistent with the theoretical expectation, the experimental observation of ${B}^{\ensuremath{-}}\ensuremath{\rightarrow}{D}^{**0}{\ensuremath{\pi}}^{\ensuremath{-}}$ for the broad ${D}^{**}$ states is astonishing as it requires that the color-suppressed contribution dominates over the color-allowed one, even though the former is $1/{m}_{b}$ suppressed in the heavy quark limit. In order to accommodate the data of $\overline{B}\ensuremath{\rightarrow}{D}^{**}{\ensuremath{\pi}}^{\ensuremath{-}}$, it is found that the real part of ${a}_{2}/{a}_{1}$ has a sign opposite to that in $\overline{B}\ensuremath{\rightarrow}D\ensuremath{\pi}$ decays, where ${a}_{1}$ and ${a}_{2}$ are the effective parameters for color-allowed and color-suppressed decay amplitudes, respectively. The decay constants and form factors for ${D}^{**}$ and the Isgur-Wise functions ${\ensuremath{\tau}}_{1/2}(\ensuremath{\omega})$ and ${\ensuremath{\tau}}_{3/2}(\ensuremath{\omega})$ are extracted from the data of $B\ensuremath{\rightarrow}{D}^{**}\ensuremath{\pi}$ decays. The Isgur-Wise functions calculated in the covariant light-front quark model are in good agreement with experiment. The neutral modes ${\overline{B}}^{0}\ensuremath{\rightarrow}{D}^{**0}{\ensuremath{\pi}}^{0}$ for ${D}^{**}={D}_{0}^{*}(2400)$, ${D}_{1}^{\ensuremath{'}}(2430)$, and ${\overline{B}}^{0}\ensuremath{\rightarrow}{D}_{1}^{\ensuremath{'}0}(2430)\ensuremath{\omega}$ are predicted to have branching ratios of order ${10}^{\ensuremath{-}4}$ which are also supported by the isospin argument. The decay constants of ${D}_{s0}^{*}(2317)$ and ${D}_{s1}^{\ensuremath{'}}(2460)$ are inferred from the measurements of $\overline{B}\ensuremath{\rightarrow}{D}_{s}^{**\ensuremath{-}}D$ to be 58\char21{}86 MeV and 130\char21{}200 MeV, respectively. Contrary to the decay constants ${f}_{{D}_{0}^{*}}$ and ${f}_{{D}_{1}^{\ensuremath{'}}}$ which are similar in size, the large disparity between ${f}_{{D}_{s0}^{*}}$ and ${f}_{{D}_{s1}^{\ensuremath{'}}}$ is surprising and unexpected.