A Conversation about Beans

As usual, I was looking at something and started wondering about its name. I have several Castor Bean plants (Ricinus communis) because they're freakishly tropical and used to be a very popular garden plant. They've fallen out of favor for a number of reasons, like their size and oddball flowers and the burs that hold the seeds, and because they're famously the source of a poison popular with Soviet Autocrats. But they're still pretty interesting in my flower garden, which tends to a Victorian Garden style. What I started thinking about was whether they're related to two more of my favorite ornamental plants, the Hyacinth Bean and the Scarlet Runner Bean. As usual, my curiosity led me down a very winding path.

It turns out that botanists consider the Scarlet Runner (Phaesolus coccineus) and the Hyacinth Bean (Lablab purpureus)to be true beans, as both are legumes. Otherwise, though, the three plants are wildly different in many ways, even though their beans/seeds all look a lot alike.

The outlier of this trio is the Castor Bean. The markings on its seed look very much like those on common dried beans you see in the packages for soup making. The difference is that the Castor bean seed is shaped more like an engorged tick because it has an appendage called a caruncle that looks like an insect head. Everything about the castor bean is poisonous, even though it is the source for Castor Oil... through a rigorous extraction process not to be tried at home. The seeds are protected inside a sharply burred hard casing like a chestnut, so not easily accessed by children or pets. It is a member of the Euphorbia family and not related to legumes at all.

So what about the others? Lablab , or Hyacinth Bean, is also from tropical origins, and used as fodder and as food in India, Africa and Asia. It requires very specific methods of cooking, and the ornamental varieties are not reliably safe to eat. If you want to try cooking them, please use beans purchased from grocers or specialty stores. But as ornaments, they are unsurpassed. The flowers and pods are gorgeous shades of purple among lobed leaves on sturdy vines. They are easiest treated as annuals, and may reseed themselves. The seeds are easy to collect and store to plant again next year. Be sure to label them and keep them separate from food.

I plant Scarlet Runner Beans alongside the Hyacinth Beans and let them tumble together, the hot orangey red of the one clashing happily with the purple shades of the other. The beans are edible, but must be cooked thoroughly. Raw beans contain a chemical that makes you violently ill if you consume as few as five raw beans. Cooking removes the chemical. (BTW... the same applies for kidney beans. Who'd 'a thunk?) One of the charms of the Scarlet runner (coccineus in the name is Latin for scarlet) is that is is native to the cool mountains of Central America, therefore germinates in cooler soil to get an earlier start than most beans. It's technically a perennial and I'm going to experiment to see if I can winter them over. Space doesn't permit more description of this trio of beauties, so go ahead and Google them when you have a few minutes. They're amazing.

If you have comments or suggestions for future columns, contact me at jeanthepipper@duck.com.