A lemon cucumber is a type of common cucumber, Cucumis sativus. Related to gourds, melons, and squash, it is a member of the cucurbit family of plants. It is similar to other cucumbers in many respects but is shaped more like an apple and has a lemon-yellow color, hence the name, which does not reflect the flavor at all, but only the shape and color. It tends to be sweeter and milder than other cucumbers, and is rarely found in stores.
Like many kinds of vegetables that are sold in supermarkets, cucumbers are usually only represented by a few varieties in most stores. There are hundreds of varieties of cucumbers however, and the lemon cucumber is widely regarded as one of the best of the group known as heirloom vegetables. Heirloom vegetables are varieties with historic origins that have not been hybridized with the intent of creating the perfect specimen for commercial production. Many heirloom varieties do not keep or ship as well as commercial varieties, which is the main reason they are not often found in stores. Lemon cucumbers do not keep well once picked and begin to shrivel within a few days.
The flavor and mildness of these cucumbers more than makes up for their limited shelf life. A lemon cucumber is one of the sweetest and mildest of all cucumbers, with very low levels of the chemical that can make some cucumbers bitter and cause mild gastric upset. It has excellent flavor and is very versatile, with crisp flesh that is well suited to slicing, pickling, and use in relishes. When young, these cucumbers can be eaten without peeling, but the skin thickens somewhat as they mature. The skin it is still thinner and milder, however, than that of many other varieties, particularly the standard garden cucumber found in supermarkets.
Even within this heirloom variety, known since the late 1800s, some variation can occur. The fruit is pale when young, but develops a bright yellow or slightly yellow-orange color at maturity, which may be streaked or mottled with a lighter shade of yellow. Like many pickling types of cucumbers, it develops small black spines on the skin which can easily be rubbed off with bare fingers. The plants are a semi-bush type, with numerous short vines that can be trained to climb. The lemon cucumber is known for doing well in areas with short growing seasons or cool climates and bears fruit prolifically, often producing dozens of baseball sized cucumbers from one plant.
