Chufa (Cyperus esculentus var. sativus) was one of humanity’s earliest foods, originating in Egypt and spreading throughout southern Europe and the middle east. Chufa is also commonly known as tiger nut. It is a sedge that forms clusters of small propagative tubers. The tubers are small, but numerous and they are delicious with a sort of almond/coconut flavor. It is blended into water to create the popular Spanish drink horchata, a sort of nut milk. The tubers are delicious soaked in water and eaten raw, cooked, or ground into flour and used for baking.
Most people are more familiar with chufa’s undomesticated ancestor, yellow nutsedge, which is a nearly ubiquitous weed of the temperate world. Yellow nutsedge has become a problem in many places, as it is able to thrive in depleted soils, even in the presence of high concentrations of herbicides. It is a signature noxious weed of abused soils. Happily, domesticated Chufa, a separate botanical variety or possibly even a different species, depending on what reference you choose, is much less invasive. It rarely sets seed and its tubers are concentrated under the plant, making it less spreading.
Chufa has an uncertain legal status in Washington. As a consequence, we grow it, but don’t sell it in WA. The wild species, yellow nutsedge, is a class B noxious weed here. The information sheet provided by the Washington State Noxious Weed Control Board says of chufa: “Yellow nutsedge is closely related to chufa; some taxonomists treat them as the same species (Mulligan and Junkins 1976).” That appears to except chufa from their ruling, but while I’m willing to grow it myself, I’m don’t want to sell it while it falls under a bit of a gray area. Hopefully chufa’s legal status in Washington will be clarified at some point. It is an extremely useful crop and ought to be more widely grown here. If you live in a state other than Washington, check to make sure that you are not violating local regulations by growing chufa.
Sow tubers directly about three inches deep when the soil is 60 degrees F or warmer. If you need to sow earlier in cooler soils, soak the tubers in 70 degree F water until they become plump and then put them on the surface of some damp potting soil in a warm spot. They will usually sprout within a week or two and can then be planted into colder soil to continue growing.
Provide chufa with plenty of water during the summer. It is not drought tolerant and will go dormant if the soil dries out for long. Cultivated chufa varieties are not frost tolerant; the plants will die back. The tubers will not survive in frozen soil, but are generally hardy down to air temperatures in the low 20s as long as they don’t continue for too long. In this way, chufa is much different than the wild yellow nutsedge, which is hardy to temperatures well below freezing.
Domesticated chufa varieties rarely flower. This is the classic tradeoff that we see in cultivated tuber crops; sexual reproduction is often a “use it or lose it” proposition. Of course, it would be nice if they did, since that is what makes breeding possible. Some varieties do send up a flower spike on occasion, so there is hope. It may be possible to find conditions under which they flower more readily. Breeding between chufa and yellow nutsedge could introduce valuable traits to chufa, but risks introducing weedy ones as well.