At least one ancient author recommends casting fennel seeds before a vampire, as they are compelled to stop and count them before they may continue -- giving you vital time to make good your escape. Here is what an on-line Herbal has to say:

Fennel

Botanical: Foeniculum vulgare (GÆRT.)

Family: N.O. Umbelliferae

---Synonyms---Fenkel. Sweet Fennel. Wild Fennel.

---Parts Used---Seeds, leaves, roots

---Habitat---Fennel, a hardy, perennial, umbelliferous herb, with yellow flowers and feathery leaves, grows wild in most parts of temperate Europe, but is generally considered indigenous to the shores of the Mediterranean, whence it spreads eastwards to India. It has followed civilization, especially where Italians have colonized, and may be found growing wild in many parts of the world upon dry soils near the sea-coast and upon river-banks. It flourishes particularly on limestone soils and is now naturalized in some parts of this country, being found from North Wales southward and eastward to Kent, being most frequent in Devon and Cornwall and on chalk cliffs near the sea. It is often found in chalky districts inland in a semi-wild state.

In mediaeval times, Fennel was employed, together with St. John's Wort and other herbs, as a preventative of witchcraft and other evil influences, being hung over doors on Midsummer's Eve to warn off evil spirits. It was likewise eaten as a condiment to the salt fish so much consumed by our forefathers during Lent. Like several other umbelliferae, it is carminative

It was said to convey longevity, and to give strength and courage.

---Description---Fennel is a beautiful plant. It has a thick, perennial root-stock, stout stems, 4 to 5 feet or more in height, erect and cylindrical, bright green and so smooth as to seem polished, much branched bearing leaves cut into the very finest of segments. The bright golden flowers, produced in large, flat terminal umbels, with from thirteen to twenty rays, are in bloom in July and August.

It was formerly the practice to boil Fennel with all fish, and it was mainly cultivated in kitchen gardens for this purpose. Its leaves are served nowadays with salmon, to correct its oily indigestibility, and are also put into sauce, in the same way as parsley, to be eaten with boiled mackerel

Formerly poor people used to eat Fennel to satisfy the cravings of hunger on fast days and make unsavoury food palatable; it was also used in large quantities in the households of the rich, as may be seen by the record in the accounts of Edward I.'s household, 8 1/2 lb. of Fennel were bought for one month's supply.