As mentioned, pomegranate (Punica granatum) was thought to be one of the first plants cultivated for its beneficial properties. Traditionally the leaves, seeds, juice, flowers, bark and roots were all used for their various effects, of which some of the most important are lowering fever, treating diabetes, diarrhea and ulcers, as well as stopping bleeding and acting as a blood tonic.¹³

Fennel (Foeniculum vulgare) is a perennial herb that is highly aromatic. It has been described as having the flavor of black licorice, or anise (Pimpinella anisum), but many find it to be much milder, which makes it suitable for a variety of applications. There are three different plant parts that are used in cooking: The seeds, the stalk/bulb, and the fronds.  

There is actually literature which shows that some of the compounds found in elderberry can be helpful against prior Coronaviruses. These compounds do not function as simple immune boosters, but rather complex structures that may aid in reducing the replication of the virus (at least based on prior data with prior Coronaviruses).

Cucumber, although treated as a vegetable, is a type of botanical berry or pepo and is comprised mostly of water, about 95%, along with 2 to 3% of the daily value of numerous vitamins and minerals, and a notable amount of Vitamin K at 16% of the daily value.4,5

Plant–pollinator interactions are determined through floral scents and reward components by floral chemistry. Plants release organic volatile compounds which are secondary metabolites.  These fragrant compounds are then often extracted and used in aromatherapy as essential oils.  The purpose of these compounds serves multiple purposes for the plant, but flowers use them to entice pollinators for reproduction.