Delphinidin

In general, plants that die after going from seed to maturity within one growing season (annuals) have green, herbaceous (nonwoody) stems. Most monocots are annuals, but many dicots are also annuals.

The tissues of annual dicots are largely primary, although cambia (plural of cambium) may develop some secondary tissues. Herbaceous dicot stems have discrete vascular bundles composed of patches of xylem and phloem. The vascular bundles are arranged in a cylinder that separates the cortex from the pith, although in a few plants (e.g., foxgloves), the xylem and the phloem are produced as continuous rings (cylinders) instead of in separate bundles.

The procambium produces only primary xylem and phloem, but later, a vascular cambium arises between these two primary tissues and adds secondary xylem and phloem to the vascular bundles. In some plants, the cambium extends between the vascular bundles, appearing as a narrow ring, producing not only the conducting tissues within the bundles but also the parenchyma cells between them. In other plants, the cambium is not in an uninterrupted cylinder but is instead confined to the bundles, each of which has its own small band of cambium between the xylem and phloem.