There are many food plants in the cucurbit family. The most commonly grown are generically called squash, gourds, pumpkins, melons and cucumbers.
Some species have many different fruit and growth forms and varieties that have been selected and developed by human intervention for many thousands of years.
Historical cultural variations in naming can be quite confusing and people have used the terms squash, melon, gourd, pumpkin and cucumber for the same plant fruits.
They are usually annual or short lived perennial vining plants that have thick stems with tendrils and large five lobed leaves with substantial fleshy matted root systems,
They have fleshy water dense fruits with a thin hard skin and large seeds.
Cucurbits usually have separate female and male flowers on the same plant. (Monoecious)
Flowers usually form at the node points at the base of the leaf stalks.
They are mostly insect pollinated, but pollen can also travel via the wind.
In their growth cycle they mostly tend to have male flowers first and also then develop female fruiting flowers later as the temperatures warm up and the vines become more developed and mature. Many tend to form more female than Male flowers when day light hours start to shorten after the peak of summer.
They are sometimes able to cross pollinate with other closely related species and so need isolation when growing for reliable seed purity.
If multiple varieties from the same species are grown they must either be hand pollinated or separated by at least 400m in order to gain seed that will be true to type.
How to identify a Pumpkin.
The main common groups of edible pumpkin fruits fall into 4 main species in the genus Cucurbita.
Each species has many growth forms and varieties but have common characteristics such as seed colour and shape, and the shape and form of the fruit stems.
The stems and seeds of genus Cucurbita help to identify the species.
- Cucurbita pepo – Summer squash, zucchini, courgette, crookneck, scallop, Acorn, marrow, cocozelle – has a hard, furrowed stem with five distinct angles. It’s leaves are harsh textured, unlike the soft texture of the other species. Seeds are cream coloured with a white margin.
- Cucurbita moschata – Butternut, gramma – has a hard, hairy and slightly angular stem that flares noticeably at the fruit end. Seeds are small, beige and have a darker beige margin.
- Cucurbita maxima – Winter squash, winter pumpkin, hubbard, buttercup, Lakota – has a soft and round & corky stem. The seeds are thick with cream coloured margins and a thin cellophane coating.
- Cucurbita argyrosperma (syn mixta) – Cushaw – the stem is hard, hairy, is five angled and flares out slightly at the fruit end. Seed is white or tan with a pale margin and cracks in the seed coat on the flat sides of the seeds. Seeds also have a thin cellophane coating.
Another fairly commonly grown species of genus cucurbita is the Figleaf Gourd or Chilacayote – Cucurbita ficifolia. It forms very large sprawling vines and has large fruit that look like classic oval watermelons.
Generally cross-pollination between the five cultivated Cucurbita species does not occur. However care should be taken if growing C.mixta and C.moschata together as there are some reports of these types crossing.