How to Grow Wild Potatoes

Introduction
About Wild Potatoes
Cultivation
  Propagule Care
  Climate Tolerance
  Photoperiod
  Planting
Harvest
  Storage
Propagation
  Vegetative Propagation
  Sexual Propagation
Crop Development
Index of Species

Overview

  • There are roughly 100 species of wild potatoes; the exact number is always in flux as the taxonomy changes.
  • There are two main concentrations of wild potato species: the Andes and the mountains of central Mexico.
  • Wild potatoes are typically very small, although the plants of some species are much larger than domesticated potatoes.
  • Most wild potato species are not safe to eat, other than in very small amounts, due to high glycoalkaloid content.
  • Wild potatoes can be hybridized with domesticated potatoes to introduce new traits.
  • Wild potatoes can be propagated from tubers or seeds, but seeds are more common simply because there aren’t many people who want to grow 100 species of wild potatoes every year.

Introduction

This aspires to be a guide to growing and using potato species other than the domesticated potato, Solanum tuberosum.   While wild potatoes are often used in potato breeding, little effort has been put into improving them individually.  To my way of thinking, this is a great opportunity for hobbyist breeders. Anyone with interest could easily choose to adopt a wild potato species and become a specialist in its cultivation and breeding. By working on each species, it would be possible to produce improved varieties. By improving size and reducing glycoalkaloid content, for example, it might be possible to introduce new species to more widespread cultivation. Improved varieties might also be used more effectively to introduce traits through breeding with S. tuberosum.  Many wild traits that have been incidentally introgressed into domesticated potatoes along with targeted wild genes have proved to be valuable and, in some cases, more than the originally targeted genes (Leue 1982).

The greatest barrier to this is simply figuring out where to start. While there is abundant scientific literature about wild potato species, it is rarely summarized and is difficult for amateurs to access. I started our wild potato project in 2015 with the goal of producing summary information about each species, growing them to determine the essential details of cultivation, and taking good pictures of each species (which are almost always more useful to amateurs than botanical descriptions). I have since added the goal of making crosses, either directly or through bridge species, to S. tuberosum so that we can show what the results of first generation crosses look like.

This project is likely to take several years to complete, but I hope that when we’re done, we will have a small encyclopedia of wild species that will serve as a guide for amateur cultivation and breeding. Most of the species profiles are currently incomplete, but the details are filling in as time goes on.

Germplasm supplied by the USDA Potato Introduction Station was used in the production of these guides.

About Wild Potatoes

Description

There are approximately 100 species of wild potatoes.  For the purposes of this guide, a wild potato is a member of the genus Solanum that forms tubers.  There are also members of the genus that do not form tubers, but I’m not including any of them.  The number of wild species has been significantly reduced as a result of genetic analysis – Hawkes 1990 listed 235 species.  108 are currently listed in this guide, including nothospecies (natural hybrids between wild species) and I am probably missing some of the more obscure species.  91 species have detailed pages; the rest are not currently available in the USA, so I have not grown them.  Wild potato species only grow natively in the Americas, where they range from southern Utah in the north to about the middle of Chile in the south.  There are two main concentrations of these species: the Andes, from Venezuela to Argentina, and the highlands of central Mexico. 

Wild potato species are not often cultivated and very little is known about most of them, relative to the domesticated potatoes.  They are really interesting plants and well worth growing even if you are not interested in eating or breeding them.  Many have very attractive flowers and can make interesting ornamentals.  Others have features that should surprise and delight even the most experienced potato grower.  Wild species range from only a few inches to more than nine feet tall.  While most produce small, round tubers, some form extremely unusual long, twisting, or chained tubers.  One species is an epiphyte that grows in trees!  Many have round berries, but some produce long, conical, or pointed berries that look more like chili peppers.

Planting

In most cases, the ideal germination conditions for wild potato seeds are unknown or at least unpublished.  I typically use the same conditions to start wild potato seeds as I do domesticated potato seeds: a daytime temperature of 65 degrees F and a nighttime temperature of 55 degrees F.  These conditions work for many wild species, but that doesn’t mean that they are the best conditions.  We often see germination rates lower than 50% for wild potato species.  The germination of some species is inhibited by alternating temperatures (Bamberg 2018), while other species may benefit from inverse alternation, with warmer temperatures at night and cooler during the day.  The USDA Potato Introduction Station recommends a constant temperature of 68 degrees F for germination (Bamberg 2017b).  Some species have prolonged, slow germination, a phenomenon known as “trickle germination.”

Index of Species

Species that do not link to a profile are currently unavailable in the USA, or at least I have been unable to obtain them. I will add them in the future if I am able to find them.

Species Geographical Group Taxonomic Group Ploidy EBN
S. acaule South American   Tetraploid 2
S. acroglossum South American
  Diploid 2
S. acroscopicum South American   Diploid ?
S. x aemulans South American   Tetraploid 2
S. agrimonifolium North American
  Tetraploid 4
S. ajanhuiri South American   Diploid ?
S. albicans South American   Hexaploid 4
S. albornozii South American   Diploid 2
S. anamatophilum South American   Diploid 2
S. andreanum South American   Diploid, Triploid 2
S. aracc-papa South American   ? ?
S. augustii South American   Diploid 1
S. ayacuchense South American   Diploid 2
S. berthaultii South American   Diploid 2
S. blanco-galdosii South American   Diploid 2
S. boliviense South American   Diploid 2
S. bombycinum South American   Tetraploid ?
S. brevicaule South American   Diploid 2
S. brucheri South American   ? ?
S. buesii South American   Diploid 2
S. bulbocastanum North American   Diploid 1
S. burkartii South American   Diploid ?
S. cajamarquense South American   Diploid ?
S. candolleanum South American   Diploid 2
S. cantense South American   Diploid ?
S. cardiophyllum North American   Diploid 1
S. chacoense South American   Diploid, Triploid 2
S. chilliasense South American   Diploid ?
S. chiquidenum South American   Diploid ?
S. chomatophilum South American   Diploid ?
S. clarum North American   Diploid ?
S. colombianum South American   Diploid, Tetraploid 2
S. commersonii South American   Diploid 1
S. contumazaense South American   Diploid 2
S. curtilobum South American   Pentaploid 4
S. demissum North American   Hexaploid 4
S. doddsii South American   ? ?
S. dolichocremastrum South American   Diploid 1
S. x edinense North American   Pentaploid ?
S. ehrenbergii North American   Diploid 1
S. flahaultii South American   Tetraploid ?
S. gandarillasii South American   Diploid ?
S. garcia-barrigae South American   Tetraploid ?
S. gracilifrons South American   Diploid ?
S. guerreroense North American   Hexaploid ?
S. hastiforme South American   Diploid ?
S. hintonii North American   Diploid ?
S. hjertingii North American   Tetraploid ?
S. hougasii North American   Hexaploid ?
S. huancabambense South American   Diploid 2
S. humectophilum South American   Diploid 1
S. hypacrarthrum South American   Diploid 1
S. immite South American   Diploid 1
S. incasicum South American   Diploid 2
S. infundibuliforme South American   Diploid 2
S. iopetalum North American   Hexaploid 2
S. jamesii North American   Diploid 1
S. juzepczukii South American   Triploid 2
S. kurtzianum South American   Diploid 2
S. laxissimum South American   Diploid 2
S. lesteri North American   Diploid ?
S. lignicaule South American   Diploid 1
S. limbaniense South American   Diploid 2
S. lobbianum South American   Tetraploid 2
S. longiconicum North American   Tetraploid ?
S. maglia South American   Diploid, Triploid 2
S. malmeanum South American   Diploid 1
S. medians South American   Diploid, Triploid 2
S. x michoacanum North American   Diploid ?
S. microdontum South American   Diploid 2
S. minutifoliolum South American   Diploid 1
S. mochiquense South American   Diploid 1
S. morelliforme North American   Diploid ?
S. multiinterruptum South American   Diploid 2
S. neocardenasii South American   Diploid 2
S. neorossi South American   Diploid ?
S. neovavilovii South American   Diploid 2
S. neoweberbaueri South American   ? ?
S. nubicola South American   Tetraploid 2
S. okadae South American   Diploid ?
S. olmosense South American   Diploid 2
S. oxycarpum North American   Tetraploid 2
S. paucissectum South American   Diploid 2
S. pillahuatense South American   Diploid 2
S. pinnatisectum North American   Diploid 1
S. piurae South American   Diploid 2
S. polyadenium North American   Diploid 2
S. raphanifolium South American   Diploid 2
S. raquialatum South American   Diploid 1
S. x rechei South American   Diploid  
S. rhomboideilanceolatum South American   Diploid 2
S. salasianum South American   Diploid  
S. x sambucinum North American   Diploid  
S. scabrifolium South American   Diploid  
S. schenkii North American   Hexaploid 4
S. simplicissimum South American   Diploid 1
S. sogarandinum South American   Diploid  
S. stenophyllidium North American   Diploid 1
S. stipuloideum South American   Diploid 1
S. stoloniferum North American   Tetraploid 2
S. tarnii North American   Diploid  
S. trifidum North American   Diploid 1
S. x vallis-mexici North American      
S. venturii South American   Diploid 2
S. vernei South American   ? ?
S. verrucosum North American   Diploid 2
S. violaceimarmoratum South American   Diploid 2
S. wittmackii South American   Diploid 1
S. woodsonii North American   Tetraploid 2

Leave a Reply