Companion planting is about growing particular crops together, so that both thrive. However, this idea also works in reverse, whereby certain pairings should be avoided, as one or both will suffer when grown together. It's for this reason, there are a number of plants never to grow next to fennel.
That said, it's well worth knowing how to grow fennel. With its pretty yellow clusters of flowers, and aromatic aniseed flavor, bulbing fennel (aka Florence fennel) is a fabulous plant for kitchen gardens and flower beds. A member of the Apiaceae family, fennel grows in zones 3-10 and is known to attract pollinators and beneficial bugs - which can keep garden pests under control naturally.
