All butter beans are limas, but not all limas are butter beans.
Actually, it’s a lot more complicated. While lima beans and butter beans are usually thought of as two different types of beans, they are both varieties of Phaseolus lunatus (literally “moon bean”), which has a very complicated history of domestication in Meso- and South America.
During the Spanish Viceroyalty of Peru (16th-19th centuries), when limas were exported to North America and Europe, the boxes of beans were stamped with their place of origin (“Lima, Peru“), and the beans got named as such. But of course, when referring to the bean, the word is pronounced LY-mah, while the Peruvian capital is (as you all know) pronounced LEE-mah.
As a rule, large, yellow/white/speckled limas are generally known as butter beans, while the smaller, green varieties are called, well, limas. The smallest may even be called “baby” limas. However, I have been told that “they call butter beans limas up North,” which puts another spin on it.
Limas are a warm-weather crop and come into season sometime around mid-June and, with the planting of second crops in late July and early August, stay in season well into October.
Among the most popular varieties grown in Mississippi are ‘Thorogreen’ and ‘Henderson,’ both small green bush types; ‘Jackson Wonder,’ also a bush variety, is small and brown or speckled; ‘Florida Speckled’ is a larger pole variety, and the hard-to-find ‘Willow Leaf,’ also a pole variety, has something of a cult following. Butterpeas are a type of lima beans.
Fresh beans should be smooth and plump, somewhat tacky to the touch. Fresh beans should be washed and picked over for damage, dirt, or detritus, washed, and set to cook in water 2:1; fresh beans don’t need as much water as dried, and they don’t need pre-soaking. As with most beans, hambone is a classic addition, but many people use stock.
Bring beans to a boil, then lower heat to simmer and cover until beans are soft. I always use white pepper instead of black to season, and rarely use anything more until the beans are cooked, at which point they become the basis for any number of wonderful dishes.
Every summer I make baked limas in sour cream. For a pound of cooked limas with about a half cup of the liquid, add a quarter cup of brown sugar, and a cup of sour cream mixed with a teaspoon corn starch to keep it from separating. Flour will work in a pinch. Mix well. Bake in a low oven until set. This dish goes with anything at all but is open to any number of frivolous variations.