The bean your grandmother kept
In 2011 a plant breeder in Delaware said something surprising about the lima beans there. Some of them, she reported, were still being grown from seed that families had chosen and kept themselves.
Delaware is not a big state and it has no spare room, so how does a crop that wants a whole field fit into it at all? One way: the field does not belong to the lima beans alone. USDA’s own crop profile for the state describes the arrangement: “Lima beans are double-cropped on as much as three-fourths of the acreage, thus offering producers maximum utilization of the land,” and “Limas are often planted in June or July after a pea or small grain crop.” Even the machinery is shared — “The same harvesting equipment is used for peas (Pisum sativum L.) and lima beans, so capitalization costs can be spread over two crop years.” One field, two crops, one harvester. The other thing the profile keeps returning to is the weather, and it is blunt about it. Heat is the problem: “Temperatures of 90 degrees Fahrenheit or above reduce pollination and pod set.” Damp air is the fix: “High humidity favors pollination and pod set and is one reason lima beans have been grown successfully in Delaware,” and “Fogs, heavy dews, and their moderating effects on temperature are helpful in pollination and pod set.” A crop that wants fog, planted late enough to miss the worst of the summer. That is what the profile records about growing limas in this state. Whether it is also why Delaware ends up at the top of the USDA table in the quiz, the profile does not say — and neither does this note.
Basis: USDA Regional IPM Centers, “Crop Profile for Beans (Lima) in Delaware” (prepared June 1999, revised July 2006; supported by USDA NIFA), section Cultural Practices. Quotations unchanged. The profile is a 2006 snapshot of how the crop was grown in the state.
In 2011 a University of Delaware article described two lima bean worlds in Delaware — and the quiz beside this note counts acres without telling them apart. The commercial world was machines and freezers. The article reports that “the commercial market is made up almost entirely of baby limas and Fordhooks, not pole limas,” and that “These baby limas and Fordhooks are grown for processing, which, nowadays, means flash-frozen, not canned.” The other world was a pole in a back garden. Pole limas climb: one popular local variety, the same article says, “features 16- to 20-foot-long vines bearing large, flat pods.” They are eaten fresh, which is why, in 2011, you had to go looking for them — “If you want to eat fresh lima beans this summer, you’ll need to be on the look-out for pole limas at farmers’ markets, particularly markets in Sussex or Kent counties.”
Basis: University of Delaware, UDaily, “Local varieties are a unique part of Delaware’s ‘lima bean culture’” (3 May 2011), quoting Emmalea Ernest of UD Cooperative Extension. Quotations unchanged.
And here is the genuinely unusual part — and it is a plant breeder, not this note, who points it out. Speaking in 2011, Emmalea Ernest of UD Cooperative Extension put it plainly. “At conferences, I’ve met people in the agricultural industry who have never heard of pole limas,” she said. “But there is a long tradition of growing pole limas here; there is a real lima bean culture in Delaware.” Then comes the sentence that separates this from ordinary heirloom gardening: “As a plant breeder, the most interesting thing to me about pole lima beans is that it is still possible to find people in Delaware who are growing local landrace varieties that they have selected themselves or that have been passed down in their families. For other vegetables, even though there are lots of people out there growing heirloom varieties, they got the seed from Burpee, not their grandmother.” A landrace is a variety that was never designed anywhere: it was shaped in one place, over many years, by people saving seed from whichever plants did best for them. Burpee, in that sentence, is an old American seed company. Read the comparison she is making: even growers of heirloom varieties, she says, are mostly buying the old plants, packet by packet, rather than keeping them.
Basis: University of Delaware, UDaily (3 May 2011). Quotations unchanged. The comparison with other vegetables is the plant breeder’s, reported in 2011, not this site’s. The description of what a landrace is, is the ordinary agricultural meaning of the word and is not a claim about any particular variety.
So why here? The breeder’s own comparison is what makes the question worth asking: for other vegetables, she says, even heirloom growers bought their seed. Why would these counties be different? It is easy to build a tidy chain: the crop has been in this corner of the map for generations; the growing conditions are odd enough — heat that stops pods setting, fog that helps them — that a locally chosen plant really might beat a catalogue one; and lima bean seed is about the easiest thing in the world to keep, because the seed is the bean you eat, so saving it needs no equipment at all. Every one of those pieces is plausible. Not one of the sources used for this note says which of them did it, or whether it was mostly habit and stubbornness handed along between neighbours. So it is written here as a guess. What is documented is narrower than it sounds, too: in 2011 a plant breeder working in the state reported that it was still possible to find people growing varieties their own families had selected. This note does not know how many of those growers are left today.
※ A hypothesis is an idea that isn't proven yet.
📊 Sources for the rankings mentioned in this note (links to the original data and retrieval dates) are on each quiz page below.