Arracacha (Aracacia xanthorrhiza) | Andean vegetable | Root and leaf

(This growing guide is an excerpt from The Cultivariable Growing Guide, available in this store and as a Kindle book on Amazon.)

arracacha-illustrationHow to Grow Arracacha

About Arracacha

Growing

Harvest

Propagation

Pests and Diseases

Crop Development

About Arracacha

Description

Arracacha (Aracacia xanthorrhiza), pronounced ar-ah-CAH-cha, is a member of the family Apiaceae, a relative of plants like carrot, parsnip, celery, and parsley (and, in this book, root chervil and skirret). It is sometimes called Peruvian carrot or Peruvian parsnip in English, but the perilous nature of these names should be obvious. Let’s stick to calling it arracacha.

In form and flavor, it is something like a cross between a carrot and celery. The storage roots are like a cluster of up to ten very large carrots with the aromatic flavor of celery. The stems and leaves are very similar to those of celery as well.

The plant can grow as tall as three feet (91 cm) and about as broad, although typically only about two-thirds that size in plants that are harvested after their first year. Roots can be white or yellow, sometimes with purple streaking and some interior color. Storage roots, stems, and leaves are all edible, although the roots are the most commonly consumed part.

Its native territory stretches from Venezuela to Bolivia, but it is most well known in the northern part of its range: Colombia and Venezuela. It is grown as high as 10,500 feet (3200 m), although mostly much lower than that (NRC 1989).

There may be as many as 50 varieties in the Andes. Diversity is greatest in Colombia, Venezuela, and Ecuador. Unlike many of the Andean root crops, arracacha is popular and appears to be at no risk of disappearing, although varieties containing valuable diversity in the southern part of its range (Peru, Bolivia, and especially Chile) may be at risk.

Two varieties appear to be commonly available outside the Andes: the Puerto Rican clone introduced to North America by Sacred Succulents and a variety of unknown origin introduced first to Australia by Zaytuna Farm (Joel 2013). We can only hope that a wider selection of varieties will be imported to North America in the future.

History

Arracacha is one of the more successful Andean roots; it is now widely cultivated outside the Andes, ranging from Brazil in the south to Cuba and Puerto Rico in the north.

Arracacha was introduced to Puerto Rico in 1910 and has been grown there in the higher elevations ever since (NRC 1989). The single variety currently available in North America came from Puerto Rico.

Most arracacha is grown in Brazil, Colombia, Ecuador, and Venezuela. More arracacha is now grown in Brazil, where it has been grown since the early 1900s, than in the Andes. Brazil has done a lot of breeding work with arracacha and now has relatively quick cropping varieties that are grown in warm temperate lowland areas (Hermann 1997). In Brazil, arracacha is known as batata baroa or mandioquinha salsa, literally “baron’s potato” and “cassava parsley”.

Arracacha is a perennial plant; the top growth dies back over the winter, but the plant will return year after year as long as the soil doesn’t freeze.

Apparently, the aroma of arracacha is not as delightful to some as it is to others (Hermann 1997). It is a love it or hate it odor, similarly to cilantro. I can’t imagine anyone disliking arracacha, but I love cilantro too.

Unlike many of the Andean roots, wild forms of arracacha still grow in the Andes. These undomesticated varieties contain strongly astringent substances and are basically inedible, but they could be useful for breeding.

Nutrition

arracacha-nutrition-labelArracacha is a starchy root with little protein or fiber. It is a high energy, highly digestible food that is also high in vitamin C. It is otherwise fairly low in vitamins and minerals.

Arracacha is probably not the healthiest of the Andean root crops. Of course, the objectives of subsistence agriculture and modern agriculture are different: calories are highly important when they are difficult to obtain and, with a 6.6 pound (3 kg) maximum yield, a single arracacha plant can provide as many as 3270 calories.

Figure 4: Arracacha nutrition information

Cooking and Eating

Arracacha can be prepared in any way that carrots and potatoes can be prepared. They are baked, boiled, fried, and added to soups and stews. They are processed and used in baking, either as pulps or processed down to flour or starch (NRC 1989).

Arracacha roots are only eaten cooked; they are simply too hard to eat raw. The cooked root is soft, slightly sticky, extremely dense, and has a flavor something like a combination of carrot, potato, and celery.

The stems and leaves are also edible and taste similar to celery. The strongly flavored older leaves can make a good addition to soup stock. Harvesting too many is probably not a good idea if you are hoping for good sized roots, since the plant already struggles to produce those in a short growing season.

Cultivation

Climate Tolerance

In its native range, arracacha is grown from the lower, subtropical elevations of the Andes, all the way up to 10,500 feet (3200 m), where the climate is cool and temperate. Most varieties are grown at warmer middle elevations, so good performance in cool climates should not be assumed.

The aerial plant is killed by frost, but it requires a very long growing season, up to thirteen months. Therefore, to produce a good crop in North America, extraordinary measures are necessary. Growing in a tunnel for season extension will help in many places. I grow outdoors, but start the plants in pots in February. They are transplanted to the field at the end of March and harvested in early December or following frost, should it arrive earlier.

Although it will tolerate relatively warm weather for an Andean crop, arracacha seems to like temperatures in the mid 50s to mid 70s F (10 to 25 C) best. It suffers in prolonged temperatures above 90° F (32 C). Below 50° F, arracacha grows so slowly that it requires two full growing seasons to produce worthwhile storage roots.

Arracacha can probably be grown as an annual in USDA zones 8b and warmer, although full yields are definitely not guaranteed.

The crop requires moderate water. It is tolerant to drought, but drought may force the plant into a reproductive mode, ruining the storage root yield. Should this happen to you, there is no reason to be disappointed; arracacha seed is very difficult to obtain. If you don’t have a use for it, sell it to me!

Arracacha is reasonably shade tolerant; it probably evolved as an understory plant. That said, you need every scrap of sunlight you can get to produce a good yield in North America, so grow it in full sun if you plan to eat the roots.

Arracacha can be grown in the Pacific Northwest with some work, such as starting plants indoors and protecting them from frost toward the end of the growing season. It should perform well in coastal California, Florida, and probably parts of the Gulf coast. Any climate that is frost free without scorching summer temperatures is probably worth a try.

Photoperiod

Photoperiodism of arracacha is not well studied and some sources suggest that it may form storage roots most quickly under short day conditions. The variety available in the United States appears to be day neutral as far as I can tell, although I don’t have a lot of leeway in timing its growing period, so I might not be able to detect photoperiod differences.

Soil Requirements

Arracacha is not particularly demanding of soil fertility, as it is often grown following a potato crop without further amendment (Hermann 1997). It likes well drained, even sandy soils. It performs very well for us in 12 inches (30 cm) of sandy loam over clay. It will grow in moderately acidic to mildly basic soils.

Propagule Care

Arracacha offsets are highly perishable. They will survive long enough to be mailed, but not much longer than that. They should be potted for storage in slightly damp soil and stored at about 50° F (10 C). They will begin growing within a few weeks even at this temperature, so be prepared to care for house plants until conditions are suitable for transplant.

Planting

In row cropping, arracacha should be planted on roughly two foot (60 cm) centers in row, with three feet (90 cm) in between rows. This will leave just enough room to move between rows when the canopy closes.

Offsets should be pre-rooted. Although they are often started directly in the field in the Andes, shorter North American growing seasons demand more care. Pot the offset in damp soil, watering frequently enough to keep the soil moist but not soaking wet. The offset will root sufficiently for transplant to the field in about six weeks.

Harden off the potted offsets for several days and then transplant to the field at the same level they were planted in the pot.

Management

In South America, any flower stalks are promptly removed in order to preserve root yield. Plants are slightly hilled if the storage roots become exposed, as they are extremely vulnerable to pests. Otherwise, the plants require little specialized care.

Companion Planting

I have no experience companion planting with arracacha. Given its long growing season, it would probably pair well with something shallow rooted and undemanding like annual herbs or leafy greens.

Growing as a Perennial

Growing arracacha as a perennial in most of North America will be a technical challenge. It is not feasible where the ground freezes even a small amount; the root stock is easily damaged by freezing. In frost free climates, it can be left in the ground for more than one year, which may increase yields, although frost free climates are usually warm enough that the plants may not need additional time to form a good yield.

Container Growing

Arracacha is said to produce little to no storage roots when grown in containers (Hermann 1997). This is unfortunate, since container growing would be one way to extend the growing season. Obviously container size must play some role, but this suggests that containers must be large and perhaps that soil temperature must be kept fairly cool.

Harvest

arracaca-entireArracacha requires roughly 10 to 13 months to reach maturity (NRC 1989). This feature makes it unfortunately difficult to grow in most of North America. The plant can be harvested in as little as six months, providing a small yield of carrot like roots, but the total yield is less than 20% of what can be achieved in a full growing season. Individual roots may weigh as much as 2.2 pounds (1 kg), although they are generally smaller (Hermann 1997). With a full growing season, per plant yields may be as high as 6.6 pounds (3 kg) (NRC 1989). I haven’t yet achieved even half a pound (227 g).

Historically, arracacha was grown in successive plantings and harvested in small batches as needed (Bristol 1988), a consequence of its perishability.

Offsets for the next growing season must be taken when the roots are harvested. They can be left attached to the root stock, but losses are greater than when they are immediately detached and rooted.

Storage

The optimum storage temperature for arracacha roots is 50° F (10 C), at which they can be stored for 28 days before loss of quality begins to become apparent (Ribeiro 2005). When stored significantly above or below this temperature, they quickly degrade in quality. Arracacha roots should probably not be washed, as this can reduce the already short storage life (Hermann 1997).

Preservation

As far as I know, arracacha is never canned, but is often dried. Many processed food products are made with arracacha pulp, starch, and flour.

Propagation

Arracacha is normally propagated vegetatively, with offsets. It can also be propagated by seed, but as a polyploid, it does not grow true, so seed is primarily useful for breeding.

Vegetative Propagation

Due to its polyploid nature, the only way to maintain varieties is to propagate them with offsets.

Offsets form from the central rootstock of the plant. These offsets can be detached and rooted. The simplest procedure is to plant them directly in damp soil, but experienced growers take more care in preparing the offsets. Trimming the offsets down to only two or three buds is said to reduce the size of the plant, but increase the size of the storage roots (Hermann 1997). For best results, the cuts should be allowed to heal for a day or two in a humid environment and the offsets should then be potted to root.

Sexual Propagation

Arracacha rarely flowers, although this characteristic differs from one variety to another. It appears that flowering is primarily triggered by environmental stress. Arracacha flowers with greater frequency in Brazil, where low temperatures and dry conditions may be responsible (Hermann 1997). Of course, the varieties grown in Brazil were bred there from seed, which also seems likely to have had some influence on the flowering frequency of the progeny.

Flowering has been forced in some arracacha varieties by dehydrating mature crowns by 20 to 30 percent (Hermann 1997). Unfortunately, I have tried this with the Puerto Rican clone available in North America without success. We should keep trying though! Obtaining seed would unlock arracacha for breeding work, which will be critical to adapting the plant to our shorter growing seasons.

Arracacha is a tetraploid and progeny from self pollinated seeds demonstrate a considerable degree of variability. It is probably a facultative outbreeder, capable of self pollination, but with better seed set following cross pollination. Germinability of even fresh seed is quite low, 30% or less (Hermann 1997).

Problems

Pests

The usual enemies of Andean roots in North America apply here: slugs and voles. Take care to keep the storage roots covered with soil to defend against slug damage. Voles are trickier. They may prefer arracacha to any other root crop. I have been experimenting with surrounding arracacha with mashua (which voles do not like) and the early results look promising.

Diseases

No information regarding diseases of arracacha in North America is available, given the minimal cultivation of this crop. In Brazil, the major disease is a rot caused by the bacterium Erwinia carotovora. The disease begins with small, water soaked depressions on the storage roots which rapidly expand and develop a foul odor (Romeiro 1988). This is a nearly ubiquitous pathogen of many crop plants and so is likely to present similar problems for arracacha cultivation in North America. It is a systemic infection that remains in the offsets to infect the next generation of clones (Hermann 1997).

Arracacha is also affected by a number of viruses. One of these viruses also infects potato, oca, and ulluco. As always, be careful when introducing new varieties because one imported virus could become a problem for several of the Andean root crops.

Defects

Arracacha plants appear to be quite regular in form and resilient to our climate conditions. I have observed no unusual problems during the growing season.

Crop Development

To begin with, there can really be only one goal: good root production in a shorter season. Almost all of North America is unsuitable for field cultivation of arracacha. While it can be kept alive on a small scale, it has no potential as an economically important crop at this point. Brazil has brought the cropping time down to as little as seven months through a combination of breeding and cultural practices. We should be able to do that too. The job would be a lot easier if we could import plants or seeds from South America.

Varieties

There is only a single variety that is generally available in North America: an unnamed clone from Puerto Rico. It has performed well for us so far, but I haven’t been working with it for long. It is a full season type and needs at least 11 months from sprouting to harvest.